Covington, MF; Chin, SS; Osborn, AG (December 2011). "Pituicytoma, spindle cell oncocytoma, and granular cell tumor: clarification and meta-analysis of the world literature since 1893.". American Journal of Neuroradiology32 (11): 2067–2072. PMID21960498. doi:10.3174/ajnr.A2717.
Covington, MF; Chin, SS; Osborn, AG (December 2011). "Pituicytoma, spindle cell oncocytoma, and granular cell tumor: clarification and meta-analysis of the world literature since 1893.". American Journal of Neuroradiology32 (11): 2067–2072. PMID21960498. doi:10.3174/ajnr.A2717.