Van Gogh Museum, Amsterdam: To Theo van Gogh. Arles, Monday, 3 September 1888.. [dostęp 2011-03-31]. Cytat: „Yesterday I spent another day with that Belgian – who also has a sister among the Vingtistes (...) – at last I have a first sketch of that painting I’ve been dreaming about for a long time – the poet. He posed for it for me. His fine head, with its green gaze, stands out in my portrait against a starry, deep ultramarine sky; his clothing is a little yellow jacket, a collar of unbleached linen, a multicoloured tie. He gave me two sittings in one day.”(ang.).
Van Gogh Museum, Amsterdam: To Willemien van Gogh. Arles, Sunday, 9 and about Friday, 14 September 1888.. [dostęp 2011-03-31]. Cytat: „I have one to start with, the portrait of a young Belgian Impressionist; I’ve painted him as something of a poet, his refined and nervous head standing out against a deep ultramarine background of the night sky, with the twinkling of the stars.”(ang.).
