1Castanet J, Smirina EM, 1990. Introduction to the skeletochro- nological method in amphibians and reptiles. Annales de Sci- ences Naturelles, Zoologie 11: 191-196.
2Chen W, Yu TL, Lu X, 2011. Age and body size ofRana kukunoris, a high-elevation frog native to the Tibetan plateau. Her- petological Journal 21:149-151.
3Czarnoteski M, Koztowski J, 1998. Do Bertalanffy's growth curves result from optimal resource allocation? Ecology Let- ters 1: 5-7.
4Eaton BR, Paszkowski CA, Kristensen K, Hiltz M, 2005. Life-history variation among populations of Canadian toads in Alberta, Canada. Canadian Journal of Zoology 83: 1421-1430.
5Fei L, Ye CY, Jiang JP, 2010. Colored Atlas of Chinese Am- phibians. Chengdu: Sichuan Publishing House of Science and Technology.
6Guarino FM, Angelini F, Cammarota M, 1995. A skeletochro- nological analysis of three syntopic amphibian species from southern Italy. Amphibia-Reptilia 16: 297-302.
7Guarino FM, Erismis UC, 2008. Age determination and growth by skeletochronology of Rana holtzi, an endemic frog from Tur- key. Italian Journal of Zoology 73: 237-242.
8Howard RD, 1981. Sexual dimorphism in bull frogs. Ecology 62: 303-310.
9Khonsue W, Matsui M, Hirai T, Misawa Y, 2001. A comparison of age structures in two populations of the pond frog Rana ni- gromaculata (Amphibia: Anura). Zoological Science 18: 597-603.
10Khonsue W, Matsui M, Misawa Y, 2000. Age determination by skeletochronology of Ratza nigrovittata, a frog from tropical forest of Thailand. Zoological Science 17: 253-257.