reftex-arg-cite
reftex-arg-cite is an autoloaded Lisp function in `reftex-auc.el
'.
(reftex-arg-cite OPTIONAL &optional PROMPT DEFINITION)
Use `reftex-citation' or AUCTeX's code to insert a cite-key macro argument.
What is being used depends upon `reftex-plug-into-AUCTeX'.