1. Basketry in Frightful Cave
2. AGURELL, S, CACTACEAE ALKALOIDS .1., LLOYDIA 32: 206 (1969).
3. Mem. Inst. Nac. Antropol. Hist. 1962 5
4. Conociendo a Coahuila los laguneros o irritilas su cultura y sus restos 1960
5. BISSET, N.G., TERTIARY ALKALOIDS OF SOME ASIAN SPECIES OF STRYCHNOS, JOURNAL OF PHARMACY AND PHARMACOLOGY 23: S244 (1971).