Thiollay (1979), Bunting and Wright (1985), Inskipp (1989a), de Roder (1989), Gurung (undated), Green (1993), King Mahendra Trust for Nature Conservation (1994, 1997, 2004, undated a,b), WWF Nepal Program (2000a, b), Suwal (2000), Inskipp and Inskipp (2001a), Inskipp and Inskipp (2003), Suwal (2003), McGowan (2004).