In 1992, a group of painters submitted a report to the National Gallery outlining their concerns about the Samson and Delilah's attribution to Rubens.

They had embarked on scholarly research into the painting some five years earlier as students at the Wimbledon School of Art in London, believing by looking closely at the Samson and Delilah as painters that it could not be by Rubens.

You can download a copy of that 1992 Report in PDF format.