Ad Dekkers ( 1938 - 1974 ) was a Dutch painter. Ad Dekkers s works have been put up for auction numerous times, with realized prices surpassing estimated prices, varying from 9140.74 USD for Vierkant gefreesd in Vierkant in 2003 to 61285.43 USD for Cirkel en Vierkant in Overgang (Circle and Square in Transition) in 2019 , based on the size and medium of the artwork.