Li, J.; Hou, Y.; Li, Y.; Zhang, J. (2012). "The latest straight-tusked elephants (Palaeoloxodon)? "Wild elephants" lived 3000 years ago in North China". Quaternary International. 281: 84–88. Bibcode:2012QuInt.281...84L. doi:10.1016/j.quaint.2011.10.039.
Li, J.; Hou, Y.; Li, Y.; Zhang, J. (2012). "The latest straight-tusked elephants (Palaeoloxodon)? "Wild elephants" lived 3000 years ago in North China". Quaternary International. 281: 84–88. Bibcode:2012QuInt.281...84L. doi:10.1016/j.quaint.2011.10.039.