A six-month investigation of Russian avant-garde paintings has found that there are more counterfeit paintings circulating in the market than genuine ones. The report, put together by journalists from ARTnews and being published online on Monday (artnewsonline.com), was based on interviews with scholars, dealers and others in the United States, Russia, Germany, France and Spain. The report looked at art galleries and auction houses throughout Europe and found that many paintings attributed to Wassily Kandinsky, Kasimir Malevich, Mikhail Larionov and others were authenticated by state museums and conservation institutes after the fall of the Soviet Union despite having unclear provenances. For example, ARTnews said, the provenances might claim the paintings came from hitherto unknown private collections or had been confiscated by the K.G.B.