[Heb-NACO] Romanization Question

[sshtuhl]

Hi all,
I have a question about the word פסיפס, which is originated from Greek. 
As a foreign-loan word it should be Romanized as 'psefas' but in entries 
it appears as 'pesefas'. Does anyone have any thoughts on this discrepancy?
Thanks,
Smadar

-- 
Smadar Shtuhl
Hebraica Library Specialist
University of Pennsylvania
Van Pelt-Dietrich Library Center
3420 Walnut Street
Philadelphia, PA 19104-6206
F. 215-573-9610
sshtuhl at upenn.edu