98. LaTeX技巧559：如何让xetex使用默认的computer modern字体？

参考：

• http://bbs.ctex.org/viewthread.php?tid=57205

• http://tex.stackexchange.com/questions/17771/computer-modern-unicode-opentype-for-xetex-fontspec

• http://tex.stackexchange.com/questions/10488/force-computer-modern-in-math-mode