Internet-Draft and RFC statistics
Hirsch index or h-index is a measure of the productivity and impact of the publications of an author . An author with an h-index of 5 has had 5 publications each cited at least 5 times - to increase the index to 6, the 5 publications plus 1 more would have to have been cited at least 6 times, each. Thus a high h-index requires many highly-cited publications.
Note that the h-index calculations do not exclude self-references.