REFERENCES
- Solow , A. R. 1993a . Inferring extinction from sighting data . Ecology , 74 : 962 – 964 .
- Solow , A. R. 1993b . Inferring extinction in a declining population . J. Math. Biol , 32 : 79 – 82 .
- Bartholomew , D. J. 1956 . J . R. Stat. Soc , 18 : 234 – 239 . 1956
- Coleman , L. and Huyghe , P. 1999 . The field guide to Bigfoot, Yeti, and other mystery primates worldwide New York : Avon Books .