diff --git a/HSlippyMap.cabal b/HSlippyMap.cabal
--- a/HSlippyMap.cabal
+++ b/HSlippyMap.cabal
@@ -2,9 +2,9 @@
 -- documentation, see http://haskell.org/cabal/users-guide/
 
 name:                HSlippyMap
-version:             1.2
+version:             1.4
 synopsis:            OpenStreetMap Slippy Map
-description:	     Use OpenStreetMap Slippy Map with Haskell : http://wiki.openstreetmap.org/wiki/Slippy_map_tilenames#Haskell
+-- description:
 homepage:            https://github.com/j4/HSlippyMap
 license:             BSD3
 license-file:        LICENSE
@@ -16,6 +16,6 @@
 cabal-version:       >=1.8
 
 library
-  exposed-modules:  HSlippyMap
-  -- other-modules:       
+  exposed-modules:   HSlippyMap
+  -- other-modules:
   build-depends:       base ==4.6.*
diff --git a/HSlippyMap.hs b/HSlippyMap.hs
--- a/HSlippyMap.hs
+++ b/HSlippyMap.hs
@@ -1,5 +1,4 @@
 module HSlippyMap (
-    -- * HSlippyMap
     Tile,
     tileFromLatLong,
     tileFromGPS
@@ -7,29 +6,27 @@
 
 type Lat = Float
 type Long = Float
-type GpsX = Integer
-type GpsY = Integer
+type X = Integer
+type Y = Integer
 type ZLevel = Integer
 
 data Tile = Tile {
   lat :: Lat,
   long :: Long,
-  x :: GpsX,
-  y :: GpsY,
+  x :: X,
+  y :: Y,
   z :: ZLevel }
 
 instance Show Tile where
   show (Tile lat long x y z) = "http://tile.openstreetmap.org/" ++ show z ++ "/" ++ show x ++ "/" ++ show y ++ ".png"
 
--- | Create Tile from Lat Long
 tileFromLatLong :: Lat -> Long -> ZLevel -> Tile
 tileFromLatLong lat lon z = Tile lat lon x y z
     where
         x = long2tilex lon z
         y = lat2tiley lat z
 
--- | Create Tile from GPS X Y
-tileFromGPS :: GpsX -> GpsY -> ZLevel -> Tile
+tileFromGPS :: X -> Y -> ZLevel -> Tile
 tileFromGPS x y z = Tile lat lon x y z
     where
         lat = tilex2long x z
diff --git a/README.md b/README.md
--- a/README.md
+++ b/README.md
@@ -1,6 +1,11 @@
 http://wiki.openstreetmap.org/wiki/Slippy_map_tilenames#Haskell
 
 ```haskell
+mapM (\z-> putStrLn $ show $ tileFromLatLong 12.3 3.3 z) [0..18]
+```
+
+
+```haskell
 long2tilex lon z = floor((lon + 180.0) / 360.0 * (2.0 ** z))
  
 lat2tiley lat z = floor((1.0 - log( tan(lat * pi/180.0) + 1.0 / cos(lat * pi/180.0)) / pi) / 2.0 * (2.0 ** z))
diff --git a/hsl.hs b/hsl.hs
--- a/hsl.hs
+++ b/hsl.hs