変分法における直接解法
↑ Dacorogna, pp. 1–43.
↑ I. M. Gelfand, S. V. Fomin (1991). Calculus of Variations. Dover Publications. ISBN 978-0-486-41448-5
↑ Dacorogna, pp. 74–79.
↑ Dacorogna, pp. 66–74.
↑ Dacorogna, pp. 87–185.