emacs参考手册也叫作elisp或 lispref 手册， 是用于emacs扩展语言的文档. gnuemacs有 emacsManual, emacsLispIntr, EmacsLispReference,三个手册，从Emacs22开始包含它们三个。 . . .
For Emacs24 and installing ac-math from Melpa (with list-packages), adding these lines in my init.el seems working: