References from the California Lichen Catalog

BREUSS, O. 2002.

Catapyrenium, pp. 125–128; Clavascidium, pp. 158–159; Endocarpon, pp. 181–187; Placidiopsis, pp. 383–384; Placidium, pp. 393–394; Placopyrenium, pp. 394–397; Thrombium, pp. 483–484, in T. H. Nash III, B. D. Ryan, C. Gries, & F. Bungartz (eds.), Lichen flora of the Greater Sonoran Desert region, Vol. 1. Lichens Unlimited, Arizona State University, Tempe.

KNUDSEN, K. 2003a.

Point Loma lichen foray, March 23, 2003. Bulletin of the California Lichen Society 10: 17–18.