found: Kerk, huwelijk en politieke macht : de zaak Lotharius II (855-869), 1997:title page (Karl Josef Heidecker; born in Aachen) cover (Karl Heidecker)
found: The divorce of Lothar II, 2010:ECIP title page (Karl Heidecker) publisher's info (born 1961) book title page (Karl Heidecker)
found: Charters and the use of the written word in medieval society, 2000:title page (edited by Karl Heidecker)
found: Die Privaturkunden der Karolingerzeit, 2009:title page (Karl Heidecker)
found: University of Groningen website, viewed October 27, 2014:link to Find a member of staff page (dr. K.J. (Karl) Heidecker; Dr. Karl J. Heidecker; Faculteit der Letteren, Middeleeuwse geschiedenis; studied History at University of Amsterdam and Paris-Sorbonne; received his doctorate from University of Amsterdam in 1997 with his thesis Kerk, huwelijk en politieke macht) - http://www.rug.nl/staff/k.j.heidecker/