CHENGDU - A Chinese panda research body Saturday announced it is working with Madrid Zoo to solicit Chinese names for twin cubs born at the zoo in September.

The Chengdu Research Base for Giant Panda Breeding invited voters to send proposed panda names along with their own names and ID codes to the email address, 83507354@163.com, before December 2.

It said in a statement that voters must be residents of Chengdu, capital of Sichuan Province. The center and officials at the Spanish zoo would jointly select the names after announcing five final entries.

The cubs, both male, were the first twin pandas born through artificial insemination outside of China.

Their mother 7-year-old Hua Zuiba, whose name means "cutie lips," and the 10-year-old father Bing Xing, meaning "ice star," were sent to Spain on a 10-year loan in 2007.

The couple never mated. Pandas are notoriously sex shy. In April, zoologists helped Hua Zuiba conceive by artificially inseminating her. She was pregnant for about 135 days.