Michael Stack (American, b. 1947) Summer Thunderhead, 1981 Oil on canvas 20 x 30 inches (50.8 x 76.2 cm) Signed and dated lower right: Michael Stack 81 PROVENANCE: Altermann Galleries, Santa Fe, New Mexico, October 22, 2005, lot 196; Private collection, Bixby, Oklahoma. HID12401132022 © 2024 Heritage Auctions | All Rights Reserved