Henk Welther ( 1911 - 1990 ) was a painter. Henk Welther s works have been put up for auction numerous times, with realized prices varying from 194.81 USD for pseudoniem van Aris Knikker in 2005 to 299.72 USD for pseudoniem van Jan Knikker jr. in 2005 , based on the size and medium of the artwork.