TETRAHEDRON, vol. 58, no. 44, page. 9019 - 9028, 2002-10-28
SYNTHESIS-STUTTGART, no. 14, page. 2191 - 2202, 2001-11
TETRAHEDRON LETTERS, vol. 41, no. 51, page. 10055 - 10060, 2000-12-16