Kao Pan is described in [Hodgson, 1967], pp 536 - 537. Tart but edible - fits [Hodgson, 1967] description of Kao Panne fairly well. (EM Nauer, 12/21/1987)
See note on this date on CRC 2242 accession card. (EM Nauer, 12/13/1989)
PI 109685 was mistakenly assigned the redundant PI 539378 in 1990; observations were made while it was assigned PI 539378, and distributions prior to today. Additional information on Kao Pan is available in Reinking and Groff (1921), Groff (1927), and Martin and Cooper (1977). (RR Krueger, 2014-06-03)
Additional information on PI 109685 from the UC Riverside Citrus Variety Collection is available here.