1. Department of Geology and Palaeontology, Muséum d'Histoire naturelle, CP 6434, 1211 Genève 6, Switzerland
2. Phu Kum Khao Dinosaur Research Centre, The Sirindhorn Museum, Sahat Sakhan District, Kalasin 46140, Thailand
3. Bureau of Palaeontological Research and Museum, Rama VI Road, Bangkok 10400, Thailand