| Pemberton, H. Earl (1983) Minerals of California. Van Nostrand Reinhold Company Inc. Murdoch, Joseph & Robert W. Webb (1966), Minerals of California, Centennial Volume (1866-1966): California Division Mines & Geology Bulletin 189: 69, 200 Reed, Ralph Daniel (1928), A siliceous shale formation from southern California: Journal of Geology: 36: 347 |