Original: A group of fossil specimens was discovered in 1923-27 during excavations at Zhoukoudian ( Chou K ` ou-tien ) near Beijing ( written ` Peking ' before the adoption of the Pinyin romanization system ) , China .
Simplified: The remains werw first discovered between in 1923 and 1937 during excavations at Zhoukoudian near Beijing , in China .