Source: https://www.amazon.com/James-Turrell-Retrospective-Michael-Govan/dp/3791352636/ref=pd_sbs_14_5?_encoding=UTF8&pd_rd_i=3791352636&pd_rd_r=KP3591ACG3555D1P6S13&pd_rd_w=Gkn7I&pd_rd_wg=dq2rx&psc=1&refRID=KP3591ACG3555D1P6S13