fixed Cite

The format of `GAPInfo.Date` has been changed recently.
`Cite` had not been adjusted to this change,
thus the number of the day got inserted instead of the year.

lib/package.gi

@@ -2830,7 +2830,7 @@ InstallGlobalFunction( BibEntry, function( arg )
  return entry;
 end );
 
-# dummy assignments to functions to be read lated in the GAPDoc package
+# dummy assignments to functions to be read later in the GAPDoc package
 ParseBibXMLextString:= "dummy";
 StringBibXMLEntry:= "dummy";
 
@@ -2888,13 +2888,10 @@ InstallGlobalFunction( Cite, function(arg)
  Print( en(StringBibXMLEntry( parse.entries[1], "BibTeX" )), "\n" );
 
  if name="GAP" then
- year:=SplitString(GAPInfo.Date,"-");
- if Length(year)=3 then 
- year:=year[3];
- else
- year:=year[1]; # to work in GAP.dev
- fi;
-
+ # The format of 'GAPInfo.Date' in released GAP is <year>-<month>-<day>.
+ # In 'GAP.dev', the value is "today".
+ year:= SplitString( GAPInfo.Date, "-" )[1];
+
  Print("If you are not using BibTeX, here is the bibliography entry produced \n",
  "by BibTeX (in bibliography style `alpha'):\n\n",
  "\\bibitem[GAP]{GAP4}\n",