A revised and updated version of
Abraham Kuyper: An Annotated Bibliography 1857-2010 by Tjitze Kuipers (2011)
You can buy a printed edition of this book on the site of the publisher.
These flyers, supposedly printed in “Eleutheropolis” [The City of Freedom] and popularly presented in the form of open letters, were intended to champion the legality and the importance of the Vrije Universiteit in the Netherlands. The first was written by “a man of the threefold cord,” while the second and third were written by “the man of the threefold cord.”
From an announcement in 1880.08 (p. 131) it appears that Kuyper did not produce these flyers, but that he composed their content either in part or in whole. The flyers were distributed by provincial correspondents and agents of the Vrije Universiteit.
The arguments put forward in the Vliegend blad [Flying paper] were countered by six issues of the Loopend blad [Running paper], supposedly published in “Haplotetopolis” [The City of Honesty], but actually published in Amsterdam by Weijtingh & Brave and printed in Amsterdam by A. Hoogeboom. The issues of the Loopend blad are dated from June 12 (must be July 12) through August 18, 1880.