Gustafson, Karl E. The crossing of heaven : memoirs of a mathematician / Karl Gustafson. - Heidelberg : Springer, c2012. - xvi, 176 p. : ill. (some col.) ; 25 cm. ISBN: 9783642225574 Subjects--Personal Names: Gustafson, Karl E. Subjects--Topical Terms: Mathematicians --United States --Biography.