"However, James T.C. Liu, a history professor from Princeton University, states that Yue Fei's version was actually written by a different person in the early 16th century. The poem was not included in the collected works of Yue Fei compiled by Yue's grandson, Yue Ke (岳柯; 1183–post 1234), and neither was it mentioned in any major works written before the Ming Dynasty. The section that states the author's wish "to stamp down Helan Pass" is what led scholars to this conclusion. Helan Pass was in Western Xia, which was not a military target of Yue Fei's armies. Liu suggests the "real author of the poem was probably Chao K'uan who engraved it on a tablet at Yueh Fei's tomb in 1502, in order to express the patriotic sentiments which were running high at that time, about four years after General Wang Yueh had scored a victory over the Oirats near the Ho-lan Pass in Inner Mongolia.""