This is BibTeX, Version 0.99dThe top-level auxiliary file: example.aux
The style file: plainnat.bst
I couldn't open database file ref.bib
---line 60 of file example.aux
 : \bibdata{ref
 :             }
I'm skipping whatever remains of this command
I found no database files---while reading file example.aux
Warning--I didn't find a database entry for "lamport94"
Warning--I didn't find a database entry for "smith05"
Warning--I didn't find a database entry for "cawley96"
(There were 2 error messages)
