diff --git a/CHANGELOG.md b/CHANGELOG.md
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -47,3 +47,6 @@
 * Third version revised A. Switched to NoImplicitPrelude extension usage. Some code improvements.
 Updated the boundaries for dependencies.
 
+## 0.3.1.1 -- 2023-01-29
+
+* Third version revised B. Some documentation improvements.
diff --git a/CaseBi/Arr.hs b/CaseBi/Arr.hs
--- a/CaseBi/Arr.hs
+++ b/CaseBi/Arr.hs
@@ -39,7 +39,6 @@
 import qualified Data.List as L (sortOn)
 import GHC.Arr
 import GHC.Exts
-import Data.Ord (comparing)
 
 {- | The function that can be used instead of the 'case ... of' function
 @
@@ -113,7 +112,7 @@
 
 {- | If it is unknown whether the list argument is sorted in the ascending order by the first element in every
 tuple (or, definitely, it is not, speaking generally), then instead of
-@ \\def xs x -> getBFst' (def, listArray (0,length xs - 1) . sortBy (comparing fst) $ xs) x @
+@ \\def xs x -> getBFst' (def, listArray (0,length xs - 1) . sortOn fst $ xs) x @
 you can use this function.
 -}
 getBFstL'
diff --git a/mmsyn2-array.cabal b/mmsyn2-array.cabal
--- a/mmsyn2-array.cabal
+++ b/mmsyn2-array.cabal
@@ -2,7 +2,7 @@
 -- documentation, see http://haskell.org/cabal/users-guide/
 
 name:                mmsyn2-array
-version:             0.3.1.0
+version:             0.3.1.1
 synopsis:            A library that can be used for multiple Ord a => a -> b transformations.
 description:         A library that can be used as a @case ... of@ construction replacement for various cases. Since the 0.2.0.0 version also uses the cuckoo hashtables in the respective module. Since the 0.3.0.0 version the hashing functionality moved to the separate package mmsyn2-hashable.
 homepage:            https://hackage.haskell.org/package/mmsyn2-array