Martyrdom of the Holy and Glorious Apostle Bartholomew - Apocryphal. According to this story, Bartholomew went to "India," where he was beheaded for having converted King Astreges' brother Polymius to Christianity. From the Ante-Nicene Fathers, vol. 8. - http://www.ccel.org/ccel/schaff/anf08.vii.xxxv.html
Bartholomew/Nathaniel - Short essay on the apostle, by Karen Rae Keck. - http://www2.evansville.edu/ecoleweb/glossary/natbar.html
Catholic Encyclopedia: St. Bartholomew - Mentioned in the lists of apostles in the Synoptic Gospels and in Acts, thought to be identical with Nathaniel (mentioned only in the Gospel of John). - http://www.newadvent.org/cathen/02313c.htm
Bartholomew the Apostle - Illustrated profile. - http://www.catholic-forum.com/saints/saintb11.htm
An Hymn upon St. Bartholomew’s Day - A poem by Thomas Traherne included in The Oxford Book of English Mystical Verse. - http://www.bartleby.com/236/50.html