Marginal printing is, I imagine, a somewhat literal translation of Drukwerk in de Marge, the Dutch for what we would call the Private Press, and De Stichting Drukwerk in de Marge is an organisation of private printers and publishers in Holland.

Editorial.

A check-list of the seventy-four (of seventy-six) King Penguins then issued was published in 1956 in The Penguin Story.

The King Penguin series.