What successful authors used a pen name rather then the in which they were born graham greeneian flemingharper lee rudyard kipling jane austin mark twain?

Let's break down the list of authors and identify those who used pen names:

* Graham Greene: Used his real name.

* Fleming: Ian Fleming used his real name for his James Bond novels, but wrote under the pen name "Michael D. Whittemore" for his early journalism and non-fiction.

* Harper Lee: Used her real name.

* Rudyard Kipling: Used his real name.

* Jane Austen: Used her real name.

* Mark Twain: Samuel Clemens used the pen name "Mark Twain."

Therefore, the authors who used pen names are:

* Ian Fleming (used "Michael D. Whittemore")

* Mark Twain (used "Mark Twain")