diff --git a/Datanalitica.package/TwitterAPI.class/instance/userEndPointFor.selecting.since..st b/Datanalitica.package/TwitterAPI.class/instance/userEndPointFor.selecting.since..st
new file mode 100644
index 0000000..bb3bd7c
--- /dev/null
+++ b/Datanalitica.package/TwitterAPI.class/instance/userEndPointFor.selecting.since..st
@@ -0,0 +1,8 @@
+as yet unclassified
+userEndPointFor: username selecting: tweetsOrMentions since: dateString
+	"I build a shared URL for querying last 100 mentions or tweets for a particular user.
+	Second parameter should be only 'tweets' or 'mentions', dateString should be YYYY-MM-DD."
+	| commonQueryParameters |
+	commonQueryParameters := '?expansions=author_id&tweet.fields=conversation_id,created_at&user.fields=username&max_results=100',
+  '&start_time=', dateString,'T00:00:00Z&'.
+	^ self usersBaseEndPoint, (self userIDFrom: username), '/', tweetsOrMentions, commonQueryParameters 
\ No newline at end of file
diff --git a/Datanalitica.package/TwitterAPI.class/instance/userTweetsFrom..st b/Datanalitica.package/TwitterAPI.class/instance/userTweetsFrom..st
index d102ea7..9c36f7e 100644
--- a/Datanalitica.package/TwitterAPI.class/instance/userTweetsFrom..st
+++ b/Datanalitica.package/TwitterAPI.class/instance/userTweetsFrom..st
@@ -2,6 +2,6 @@ accessing
 userTweetsFrom: username
 	| rawResponse queryURL |
 	"The following query gets the last 100 tweets, that is the maximun allowed for a particular user without pagination:"
-	queryURL := self usersBaseEndPoint, (self userIDFrom: username), '/tweets', self defaultQueryParameters.
+	queryURL := self usersBaseEndPoint, (self userIDFrom: username), '/tweets', self defaultQueryParameters at: 'tweets'.
 	rawResponse := self rawResponseForURL:queryURL.  
 	^ (STONJSON fromString: rawResponse)
\ No newline at end of file