diff --git a/routes b/routes
index 33692ba6f..50deecf09 100644
--- a/routes
+++ b/routes
@@ -15,26 +15,17 @@
 /course/                    CourseListR       GET
 !/course/new                CourseNewR        GET POST
 !/course/#TermId            CourseListTermR   GET
+/course/#TermId/#Text CourseR:
+  /show                       CourseShowR GET POST
+  /edit                       CourseEditR GET POST
 
--- /course/#TermId/#Text CourseR !tag:
---   /edit   CourseEditR GET POST
---   /show   CourseShowR GET POST      -- CourseR tid csh CourseShowR
---   /ex/#Text SheetR: !registered
---     /show
---     /edit                           -- CourseR tid csg (SheetR csh SheetEditR)
---     /delete
-
-/course/#TermId/#Text/edit  CourseEditR       GET
-/course/#TermId/#Text/show  CourseShowR       GET POST
-
-
-
-/course/#TermId/#Text/ex/                SheetListR   GET
-/course/#TermId/#Text/ex/#Text/show      SheetShowR   GET
-/course/#TermId/#Text/ex/#Text/#SheetFileType/#FilePath SheetFileR  GET
-/course/#TermId/#Text/ex/new             SheetNewR   GET POST
-/course/#TermId/#Text/ex/#Text/edit      SheetEditR  GET POST
-/course/#TermId/#Text/ex/#Text/delete    SheetDelR   GET POST
+  /ex SheetR !registered:
+    /                         SheetListR GET
+    /new                      SheetNewR  GET POST !lecturer
+    /#Text/show               SheetShowR GET
+    /#Text/#SheetFileType/#FilePath SheetFileR GET
+    /#Text/edit               SheetEditR GET POST !lecturer
+    /#Text/delete             SheetDelR  GET POST !lecturer
 
 /submission                 SubmissionListR GET POST
 /submission/#CryptoUUIDSubmission SubmissionR GET POST
diff --git a/src/Foundation.hs b/src/Foundation.hs
index a3d7d7e4c..474c51c13 100644
--- a/src/Foundation.hs
+++ b/src/Foundation.hs
@@ -4,6 +4,7 @@
 {-# LANGUAGE MultiParamTypeClasses #-}
 {-# LANGUAGE TypeFamilies #-}
 {-# LANGUAGE ViewPatterns #-}
+{-# LANGUAGE PatternSynonyms #-}
 {-# LANGUAGE DataKinds #-}
 {-# LANGUAGE RecordWildCards #-}
 {-# LANGUAGE NamedFieldPuns #-}
@@ -53,6 +54,9 @@ import System.FilePath
 
 import Handler.Utils.Templates
 
+-- infixl 9 :$:
+-- pattern a :$: b = a b
+
 -- | The foundation datatype for your application. This can be a good place to
 -- keep settings and values requiring initialization before your application
 -- starts running, such as database connections. Every handler will have
@@ -80,7 +84,9 @@ data UniWorX = UniWorX
 -- type Widget  = WidgetT  UniWorX IO ()
 mkYesodData "UniWorX" $(parseRoutesFile "routes")
 
-type DB a = YesodDB UniWorX a
+-- Pattern Synonyms for convenience
+pattern CSheetR tid csh ptn = CourseR tid csh (SheetR ptn)
+
 
 data MenuItem = MenuItem
     { menuItemLabel :: Text
@@ -95,7 +101,8 @@ data MenuTypes
     | NavbarExtra     { menuItem :: MenuItem }
     | NavbarSecondary { menuItem :: MenuItem }
 
--- | A convenient synonym for creating forms.
+-- | Convenient Type Synonyms:
+type DB a = YesodDB UniWorX a
 type Form x = Html -> MForm (HandlerT UniWorX IO) (FormResult x, Widget)
 
 mkMessage "UniWorX" "messages" "de"
@@ -151,7 +158,7 @@ instance Yesod UniWorX where
     isAuthorized  TermShowR          _ = return Authorized
     isAuthorized  CourseListR        _ = return Authorized
     isAuthorized (CourseListTermR _) _ = return Authorized
-    isAuthorized (CourseShowR _ _)   _ = return Authorized
+    isAuthorized (CourseR _ _ CourseShowR) _ = return Authorized
     isAuthorized (CryptoUUIDDispatchR _) _ = return Authorized
     isAuthorized  SubmissionListR    _ = isAuthenticated
     isAuthorized  SubmissionDownloadMultiArchiveR _ = isAuthenticated
@@ -205,14 +212,14 @@ isAuthorizedDB (SubmissionDownloadArchiveR (splitExtension -> (baseName, _))) _
 isAuthorizedDB TermEditR               _ = adminAccess Nothing
 isAuthorizedDB (TermEditExistR _)      _ = adminAccess Nothing
 isAuthorizedDB CourseNewR              _ = lecturerAccess Nothing
-isAuthorizedDB (CourseEditR t c)       _ = courseLecturerAccess . entityKey =<< getBy404 (CourseTermShort t c)
-isAuthorizedDB (SheetListR  t c)  False  = return Authorized --
-isAuthorizedDB (SheetShowR  t c s)     _ = return Authorized -- TODO: nur für angemeldete Kursteilnehmer falls sichtbar, sonst nur Lectrurer oder Korrektor
-isAuthorizedDB (SheetFileR  t c s _ _) _ = return Authorized -- TODO: nur für angemeldete Kursteilnehmer falls sichtbar, sonst nur Lectrurer oder Korrektor
-isAuthorizedDB (SheetListR  t c)       _ = courseLecturerAccess . entityKey =<< getBy404 (CourseTermShort t c)
-isAuthorizedDB (SheetNewR   t c)       _ = courseLecturerAccess . entityKey =<< getBy404 (CourseTermShort t c)
-isAuthorizedDB (SheetEditR  t c s)     _ = courseLecturerAccess . entityKey =<< getBy404 (CourseTermShort t c)
-isAuthorizedDB (SheetDelR   t c s)     _ = courseLecturerAccess . entityKey =<< getBy404 (CourseTermShort t c)
+isAuthorizedDB (CourseR t c CourseEditR)       _ = courseLecturerAccess . entityKey =<< getBy404 (CourseTermShort t c)
+isAuthorizedDB (CourseR t c (SheetR SheetListR))  False  = return Authorized --
+isAuthorizedDB (CourseR t c (SheetR SheetListR)) _       = courseLecturerAccess . entityKey =<< getBy404 (CourseTermShort t c)
+isAuthorizedDB (CourseR t c (SheetR (SheetShowR s))) _   = return Authorized -- TODO: nur für angemeldete Kursteilnehmer falls sichtbar, sonst nur Lectrurer oder Korrektor
+isAuthorizedDB (CourseR t c (SheetR (SheetFileR s _ _))) _ = return Authorized -- TODO: nur für angemeldete Kursteilnehmer falls sichtbar, sonst nur Lectrurer oder Korrektor
+isAuthorizedDB (CourseR t c (SheetR SheetNewR))          _ = courseLecturerAccess . entityKey =<< getBy404 (CourseTermShort t c)
+isAuthorizedDB (CourseR t c (SheetR (SheetEditR s)))     _ = courseLecturerAccess . entityKey =<< getBy404 (CourseTermShort t c)
+isAuthorizedDB (CourseR t c (SheetR (SheetDelR  s)))     _ = courseLecturerAccess . entityKey =<< getBy404 (CourseTermShort t c)
 isAuthorizedDB (CourseEditIDR cID)     _ = do
   courseId <- decrypt cID
   courseLecturerAccess courseId
@@ -285,15 +292,15 @@ instance YesodBreadcrumbs UniWorX where
 
   breadcrumb  CourseListR              = return ("Kurs", Just HomeR)
   breadcrumb (CourseListTermR term)    = return (toPathPiece term, Just TermShowR)
-  breadcrumb (CourseShowR term course) = return (course, Just $ CourseListTermR term)
+  breadcrumb (CourseR term course CourseShowR) = return (course, Just $ CourseListTermR term)
   breadcrumb  CourseNewR               = return ("Neu", Just CourseListR)
-  breadcrumb (CourseEditR _ _)         = return ("Editieren", Just CourseListR)
+  breadcrumb (CourseR _ _ CourseEditR)         = return ("Editieren", Just CourseListR)
 
-  breadcrumb (SheetListR tid csh)      = return ("Übungen",Just $ CourseShowR tid csh)
-  breadcrumb (SheetNewR  tid csh)      = return ("Neu",    Just $ SheetListR  tid csh)
-  breadcrumb (SheetShowR tid csh shn)  = return (shn,      Just $ SheetListR  tid csh)
-  breadcrumb (SheetEditR tid csh shn)  = return ("Edit",   Just $ SheetShowR  tid csh shn)
-  breadcrumb (SheetDelR  tid csh shn)  = return ("DELETE", Just $ SheetShowR  tid csh shn)
+  breadcrumb (CourseR tid csh (SheetR SheetListR))       = return ("Übungen",Just $ CourseR tid csh CourseShowR)
+  breadcrumb (CourseR tid csh (SheetR SheetNewR ))       = return ("Neu",    Just $ CourseR tid csh $ SheetR SheetListR)
+  breadcrumb (CourseR tid csh (SheetR (SheetShowR shn))) = return (shn,      Just $ CourseR tid csh $ SheetR SheetListR)
+  breadcrumb (CourseR tid csh (SheetR (SheetEditR shn))) = return ("Edit",   Just $ CourseR tid csh $ SheetR $ SheetShowR shn)
+  breadcrumb (CourseR tid csh (SheetR (SheetDelR  shn))) = return ("DELETE", Just $ CourseR tid csh $ SheetR $ SheetShowR shn)
 
   breadcrumb SubmissionListR = return ("Abgaben", Just HomeR)
   breadcrumb (SubmissionR _) = return ("Abgabe", Just SubmissionListR)
diff --git a/src/Handler/Course.hs b/src/Handler/Course.hs
index 07597838c..aebfe8634 100644
--- a/src/Handler/Course.hs
+++ b/src/Handler/Course.hs
@@ -40,7 +40,7 @@ getCourseListTermR tidini = do
             let c   = entityVal ckv
                 shd = courseShorthand c
                 tid = courseTermId c
-            in [whamlet| <a href=@{CourseShowR tid shd}>#{shd} |] )
+            in [whamlet| <a href=@{CourseR tid shd CourseShowR}>#{shd} |] )
 --         , headed "Institut" $ [shamlet| #{course} |]
         , headed "Beginn Anmeldung" $ fromString.(maybe "" formatTimeGerWD).courseRegisterFrom.entityVal
         , headed "Ende Anmeldung"   $ fromString.(maybe "" formatTimeGerWD).courseRegisterTo.entityVal
@@ -54,11 +54,11 @@ getCourseListTermR tidini = do
                 shd = courseShorthand c
                 tid = courseTermId c
             in do
-              adminLink <- handlerToWidget $ isAuthorized (CourseEditR tid shd ) False
+              adminLink <- handlerToWidget $ isAuthorized (CourseR tid shd CourseEditR) False
               -- if (adminLink==Authorized) then linkButton "Ändern" BCWarning (CourseEditR tid shd) else ""
               [whamlet|
                 $if adminLink == Authorized
-                  <a href=@{CourseEditR tid shd}>
+                  <a href=@{CourseR tid shd CourseEditR}>
                     editieren
               |]
           )
@@ -96,8 +96,8 @@ getCourseShowR tid csh = do
         [ NavbarAside $ MenuItem
           { menuItemLabel = "Übungsblätter"
           , menuItemIcon  = Nothing
-          , menuItemRoute = SheetListR tid csh
-          , menuItemAccessCallback = (== Authorized) <$> isAuthorized (SheetListR tid csh) False
+          , menuItemRoute = CSheetR tid csh SheetListR
+          , menuItemAccessCallback = (== Authorized) <$> isAuthorized (CSheetR tid csh SheetListR) False
           }
         ]
   defaultLinkLayout pageActions $ do
@@ -145,6 +145,9 @@ getCourseEditR tid csh = do
   course <- runDB $ getBy $ CourseTermShort tid csh
   courseEditHandler course
 
+postCourseEditR :: TermId -> Text -> Handler Html
+postCourseEditR = getCourseEditR
+
 getCourseEditIDR :: CryptoUUIDCourse -> Handler Html
 getCourseEditIDR cID = do
   cIDKey <- getsYesod appCryptoIDKey
@@ -256,7 +259,7 @@ courseEditHandler course = do
       (FormFailure _) -> addMessageI "warning" MsgInvalidInput
       other -> addMessage "error" $ [shamlet| Error: #{show other}|]
     let formTitle   = "Kurs editieren/anlegen" :: Text
-    let actionUrl   = CourseNewR -- CourseEditR -- TODO
+    actionUrl <- fromMaybe CourseNewR <$> getCurrentRoute
     defaultLayout $ do
       setTitle [shamlet| #{formTitle} |]
       $(widgetFile "formPage")
diff --git a/src/Handler/Sheet.hs b/src/Handler/Sheet.hs
index 77d79eefb..02ab5d510 100644
--- a/src/Handler/Sheet.hs
+++ b/src/Handler/Sheet.hs
@@ -74,7 +74,7 @@ makeSheetForm template = identForm FIDsheet $ \html -> do
       <*> areq utcTimeField  (fsb "Abgabe ab")   (sfActiveFrom   <$> template)
       <*> areq utcTimeField  (fsb "Abgabefrist") (sfActiveTo     <$> template)
       <*> fileAFormOpt       (fsb "Aufgabenstellung")
-      <*> aopt utcTimeField  (fsb "Hinweis ab")  (sfHintFrom     <$> template)
+      <*> aopt utcTimeField  (fsb "Hinweise ab")  (sfHintFrom     <$> template)
       <*> fileAFormOpt       (fsb "Hinweis")
       <*> aopt utcTimeField  (fsb "Lösung ab")   (sfSolutionFrom <$> template)
       <*> fileAFormOpt       (fsb "Lösung")
@@ -162,7 +162,7 @@ getSheetList courseEnt = do
         rated       <- count $ (SubmissionRatingTime !=. Nothing):sheetsub
         return (sid, sheet, (submissions, rated))
   let colBase = mconcat
-        [ headed "Blatt"       $ \(sid,sheet,_) -> linkButton (toWgt $ sheetName sheet) BCLink $ SheetShowR tid csh (sheetName sheet)
+        [ headed "Blatt"       $ \(sid,sheet,_) -> linkButton (toWgt $ sheetName sheet) BCLink $ CourseR tid csh $ SheetR $ SheetShowR $ sheetName sheet
         , headed "Abgabe ab"   $ toWgt . formatTimeGerWD . sheetActiveFrom . snd3
         , headed "Abgabe bis"  $ toWgt . formatTimeGerWD . sheetActiveTo   . snd3
         , headed "Bewertung"   $ toWgt . show . sheetType . snd3
@@ -170,13 +170,13 @@ getSheetList courseEnt = do
         , headed "Eingereicht" $ toWgt . fst . trd3
         ]
   let colAdmin = mconcat -- only show edit button for allowed course assistants
-        [ headed ""            $ \s -> linkButton "Edit"   BCLink $ SheetEditR tid csh $ sheetName $ snd3 s
-        , headed ""            $ \s -> linkButton "Delete" BCLink $ SheetDelR  tid csh $ sheetName $ snd3 s
+        [ headed ""            $ \s -> linkButton "Edit"   BCLink $ CourseR tid csh $ SheetR $ SheetEditR $ sheetName $ snd3 s
+        , headed ""            $ \s -> linkButton "Delete" BCLink $ CourseR tid csh $ SheetR $ SheetDelR  $ sheetName $ snd3 s
         ]
   showAdmin <- case sheets of
     ((_,firstSheet,_):_) -> do
       setUltDestCurrent
-      (Authorized ==) <$> isAuthorized (SheetEditR tid csh $ sheetName firstSheet) False
+      (Authorized ==) <$> isAuthorized (CourseR tid csh $ SheetR $ SheetEditR $ sheetName firstSheet) False
     _otherwise   -> return False
   let colSheets = if showAdmin
         then colBase `mappend` colAdmin
@@ -185,7 +185,7 @@ getSheetList courseEnt = do
         [ NavbarAside $ MenuItem
           { menuItemLabel = "Neues Übungsblatt"
           , menuItemIcon  = Nothing
-          , menuItemRoute = SheetNewR tid csh
+          , menuItemRoute = CSheetR tid csh SheetNewR
           , menuItemAccessCallback = (== Authorized) <$> isAuthorized CourseNewR False
           }
         ]
@@ -211,7 +211,7 @@ getSheetShowR tid csh shn = do
       E.where_ (sheet     E.^. SheetId      E.==. E.val sid )
       -- return desired columns
       return $ (file E.^. FileTitle, sheetFile E.^. SheetFileType)
-  let fileLinks = map (\(E.Value fName, E.Value fType) -> SheetFileR tid csh shn fType fName) fileNameTypes
+  let fileLinks = map (\(E.Value fName, E.Value fType) -> CSheetR tid csh (SheetFileR shn fType fName)) fileNameTypes
 
   defaultLayout $ do
     setTitle $ toHtml $ T.append "Übung " $ sheetName sheet
@@ -325,14 +325,14 @@ handleSheetEdit tid csh template dbAction = do
             whenIsJust sfSolutionF $ insertSheetFile sid SheetSolution
             addMessageI "info" $ MsgSheetEditOk tident csh sfName
             return True
-      when saveOkay $ redirect $ SheetShowR tid csh sfName -- redirect must happen outside of runDB
+      when saveOkay $ redirect $ CSheetR tid csh $ SheetShowR sfName -- redirect must happen outside of runDB
     (FormFailure msgs) -> forM_ msgs $ (addMessage "warning") . toHtml
     _ -> return ()
   let pageTitle = maybe (MsgSheetTitleNew tident csh)
                         (MsgSheetTitle    tident csh) mbshn
   let formTitle = pageTitle
   let formText  = Nothing :: Maybe UniWorXMessage
-  actionUrl <- fromMaybe (SheetNewR tid csh) <$> getCurrentRoute
+  actionUrl <- fromMaybe (CSheetR tid csh SheetNewR) <$> getCurrentRoute
   defaultLayout $ do
     setTitleI pageTitle
     $(widgetFile "formPageI18n")
@@ -344,19 +344,19 @@ getSheetDelR tid csh shn = do
   let tident = unTermKey tid
   ((result,formWidget), formEnctype) <- runFormPost (buttonForm :: Form BtnDelete)
   case result of
-    (FormSuccess BtnAbort)  -> redirectUltDest $ SheetShowR tid csh shn
+    (FormSuccess BtnAbort)  -> redirectUltDest $ CSheetR tid csh $ SheetShowR shn
     (FormSuccess BtnDelete) -> do
       runDB $ fetchSheetId tid csh shn >>= deleteCascade
       -- TODO: deleteCascade löscht aber nicht die hochgeladenen Dateien!!!
       setMessageI $ MsgSheetDelOk tident csh shn
-      redirect $ SheetListR tid csh
+      redirect $ CSheetR tid csh SheetListR
     _other -> do
       submissionno <- runDB $ do
           sid <- fetchSheetId tid csh shn
           count [SubmissionSheetId ==. sid]
       let formTitle = MsgSheetDelTitle tident csh shn
       let formText  = Just $ MsgSheetDelText submissionno
-      let actionUrl = SheetDelR tid csh shn
+      let actionUrl = CSheetR tid csh $ SheetDelR shn
       defaultLayout $ do
         setTitleI $ MsgSheetTitle tident csh shn
         $(widgetFile "formPageI18n")
diff --git a/src/Handler/Submission.hs b/src/Handler/Submission.hs
index 3fb482691..78ec0ed4a 100644
--- a/src/Handler/Submission.hs
+++ b/src/Handler/Submission.hs
@@ -53,7 +53,7 @@ submissionTable = do
     (,,) <$> encrypt submissionId <*> encrypt submissionId <*> pure s
 
   let
-    anchorCourse (_, _, (_, _, Entity _ Course{..})) = CourseShowR courseTermId courseShorthand
+    anchorCourse (_, _, (_, _, Entity _ Course{..})) = CourseR courseTermId courseShorthand CourseShowR
     courseText (_, _, (_, _, Entity _ Course{..})) = toWidget courseName
     anchorSubmission (_, cUUID, _) = SubmissionR cUUID
     submissionText (cID, _, _) = toWidget . toPathPiece . CI.foldedCase $ ciphertext cID
diff --git a/src/Model/Types.hs b/src/Model/Types.hs
index 7201671ab..321df30b8 100644
--- a/src/Model/Types.hs
+++ b/src/Model/Types.hs
@@ -55,7 +55,7 @@ deriveJSON defaultOptions ''SheetType
 derivePersistFieldJSON "SheetType"
 
 data SheetGroup
-  = Arbitrary { maxParticipants :: Int }
+  = Arbitrary { maxParticipants :: Int } -- Distinguish Limited/Arbitrary
   | RegisteredGroups
   | NoGroups
   deriving (Show, Read, Eq)
diff --git a/templates/course.hamlet b/templates/course.hamlet
index 14e8f6ad2..94d8dbfb4 100644
--- a/templates/course.hamlet
+++ b/templates/course.hamlet
@@ -16,7 +16,7 @@
             \ bis #{formatTimeGerWD regTo}
 
     <div>
-      <form method=post action=@{CourseShowR tid csh} enctype=#{regEnctype}>
+      <form method=post action=@{CourseR tid csh CourseShowR} enctype=#{regEnctype}>
         ^{regWidget}
 
   <div .course-header__title>
diff --git a/templates/sheetShow.hamlet b/templates/sheetShow.hamlet
index ddcb31600..0d2f4090d 100644
--- a/templates/sheetShow.hamlet
+++ b/templates/sheetShow.hamlet
@@ -29,7 +29,7 @@
                   $forall fileLink <- fileLinks
                     <li>
                       $case fileLink
-                        $of SheetFileR _ _ _ typ name
+                        $of CourseR _ _ (SheetR (SheetFileR _ typ name))
                           #{toPathPiece typ}
                           <a href=@{fileLink}>#{name}
                         $of other