gnuplot-related research paper?

[KITA T. <t-...@cc...>]

Hello, all.

Do you have any recommendation of a journal paper or a proceeding paper
in English related to gnuplot internals or gnuplot applications to visualization?

One of my students is going to work on gnuplot-related development,
and he has some assignment to read English paper related to his
research subject.
# not a manual document, a journal paper is preferable.

Sorry for an off-topic.
-- 
  KITA Toshihiro
  http://t-kita.net/