It is likely that during this period Akkeringa met and became close to the artist Isaac Israëls (1865–1934).
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Witsen wrote under a pseudonym in the literary magazine De Nieuwe Gids, which he also supported financially.His circle of friends included the painters George Hendrik Breitner, Isaac Israëls, and Jan Veth and the writers Lodewijk van Deyssel, Albert Verwey, Willem Kloos, and Herman Gorter.