I think you are right there - the tech report I linked to does credit the interface to Niklas Röjemo, so I shouldn't have used the word "originator" (as you suggested "popularised" would have been better). Unfortunately the thesis doesn't seem available on the web so I can't see how much of the applicative style it introduced.
Although the whole thesis is not online, some of the papers contained in it are. This one, although it appears to be on a different topic, does have a brief introduction to Röjemo's parser combinators in section 4. He calls them monadic, even though the style is very obviously what we would now call applicative. http://reference.kfupm.edu.sa/content/h/i/highlights_from_nhc____a_space_eff... Röjemo's source code for an entire parser for Haskell (only slightly modified for newer versions of the language) is still available online too, in the source code of nhc98. http://darcs.haskell.org/york-compiler98 Regards, Malcolm