National Geographic Magazine: August 1996 - Felipe Dávalos studies the colossal heads at the Olmec site of San Lorenzo in 1967. Taking careful measurements and notes of each detail, Dávalos drew every monument from four sides (above, right). Most scholars believe the sculptures are portraits of important rulers of Mesoamericas first civilization. www.nationalgeographic.com/ngm/9608/bts/a061.html
