diff --git a/swh/provenance/mongo/README.md b/swh/provenance/mongo/README.md
index da25c85..b8e393e 100644
--- a/swh/provenance/mongo/README.md
+++ b/swh/provenance/mongo/README.md
@@ -1,44 +1,44 @@
 mongo backend
 =============
 
 Provenance storage implementation using MongoDB
 
 initial data-model
 ------------------
 
 ```json
 content
 {
     id: sha1
-    ts: int //optional
+    ts: int // optional
     revision: {<ref revision str>: [<ref path>]}
     directory: {<ref directory str>: [<ref path>]}
 }
 
 directory
 {
     id: sha1
-    ts: int  //optional
+    ts: int  // optional
     revision: {<ref revision str>: [<ref path>]}
 }
 
 revision
 {
     id: sha1
     ts: int // optional
-    preferred  <ref origin>  //optinal
+    preferred  <ref origin>  // optional
     origin  [<ref origin>]
     revision [<ref revisions>]
 }
 
 origin
 {
     id: sha1
     url: str
 }
 
 path
 {
     path: str
 }
 ```