Klerck, Th. P.E. de (red.) Stamboom Onnes-Boelema II, Groningen 1986, 18 + 791 pag., geb. [ II= sterk vermeerderde herdruk van de editie 1909 ]. Goed exemplaar.

Maagdenhuis, Provo, stakingen en acties: Collection of pamphlets, posters, leaflets, newspaperclippings, letters and university magazines concerning the actions by the student population in the years between 1968 and 1972