There has been a reaction against the depiction of Van Gogh as a saint. John Rewald was one of the first to attempt an anti-hagiography; books pointing to Van Gogh's neuroticism have continued since. Counter-claims, particularly based on Van Gogh's three volumes of letters, support Roger Fry's praise. In winter 1927/1928, a problem began that has overshadowed Van Gogh research ever since—the emergence of forgeries. Otto Wacker staged an extensive exhibition of drawings by Van Gogh, catalogued and annotated by Julius Meier-Graefe. Then in January 1928, Paul Cassirer opened a large retrospective of paintings, from which two were removed just before the opening, as their authenticity had been questioned. The suspect paintings had been provided by Otto Wacker, and a scandal ensued. In 2007, it was concluded by a team of specialists from the Van Gogh Museum in Amsterdam that the painting "Head of a Man", attributed to Van Gogh for over 70 years, was not by him, but was painted by one of his peers. The team determined that the style was inconsistent with Van Gogh's other works, and there was no mention of the painting in any of Van Gogh's known letters. There is no evidence to suggest that the painting was intentionally created as a fake Van Gogh. In February 2010, the Museum de Fundatie in the Dutch city of Zwolle discovered it owned a Van Gogh painting made in 1886, the "Le Blute-fin windmill", authenticated “beyond any doubt” by the Van Gogh Museum in Amsterdam. The museum's founder Dirk Hannema (1895–1984), who bought the anonymous painting from a Parisian art dealer in 1975 for 6,500 francs (less than 1,000 euros), was always convinced it was a Van Gogh and insured it for a sum equivalent to 35,000 euros. However, as managing director of Rotterdam’s Museum Boijmans in 1938, Hannema had purchased a number of paintings that were attributed to Johannes Vermeer, that turned out to be forgeries. Since 1937, when the Nazis confiscated his paintings in Germany, more than 40 of van Gogh's works have been stolen, in at least 15 separate incidents, at galleries across the world. In December 2002, two paintings were stolen from the Van Gogh Museum in Amsterdam, in a brutal and audacious robbery by experienced, professional thieves. Both of the stolen works were considered important - "Beach at Scheveningen in Stormy Weather" (1882) was van Gogh's first work in oil and "Congregation Leaving the Reformed Church in Nuenen" was painted by van Gogh for his mother and later adjusted after the death of his father.