Using laboratory examination techniques, the authenticity of two Rembrandt paintings was resolved. When compared to similar works of the same period, a long doubted self-portrait of ca. 1629 emerged as autograph, while a duplicate in a Tokyo private collection seems to be by Jan Lievens. On the other hand, a Saskia, which seemed impossible to resolve because of its condition, turned out to be a studio painting of ca. 1634 and was reattributed to Govert Flinck, who was Rembrandt's pupil at that time, on the basis of other early works by him. Evidence was provided by cross-sections. See also 22-617 for investigation of Saskia -- AATA