Larry,
Do you have a copy of the book
Illusies en Incidenten: De Militaire Luchtvaart en de neutraliteitshandhaving tot 10 mei 1940, by Rob de Bruin et al? 354 pages plus probably another 100 pages of appendices and notes. The event is noted on pages 162 and 163, with two photos of the aircraft (which don't show the markings well), a photo of the surviving crew at Stern's burial, and a side view of the aircraft.
I can't find a publisher (other than apparently official Dutch government), ISBN or date (my copy was inscribed by Rob in 1989).
Perhaps your Dutch colleagues can locate a copy for your files.
Edit: a number of reasonably priced copies can be found at
http://used.addall.com/
Enjoy!
Frank.