found: Jan Wellens de Cock, c2009:p. 9 (the artist's death date is established as 1521 based on De Cock's appearance in the Court of Wards, Jan. 24, 1521 and his wife being referred to as a widow by the end of 1521) p. 96 (author argues that if the artist can be linked to Jan (Dirxz) de Cock of Leyden and his son Jacop (Jansz) de Cock, existing documentation would support a birth date in the 1460's or 1470's; assuming this relationship, the author postulates a birth date for the artist of ca. 1475; matriculates from a workshop in Antwerp in 1503, as "Jan van Leyen") p. 4 of cover ( Jan Wellens de Cock (ca. 1470-1521), Antwerp artist)
found: Grove art online, May 18, 2009(Cock: Jan Wellens de Cock; b. ?Leiden, c. 1490; d. Antwerp before Jan. 19, 1527; believed to be the painter who became a master in the Antwerp Guild of St. Luke in 1503 under the name Jan van Leyen)
found: Union list of artist names, May 18, 2009(Cock, Jan de (Netherlandish painter, probably active by 1506, died before 1527; variant forms of name: Wellens, Jan; Jan van Leyden)
