Bryant, R. L., Griffiths, P., & Grossman, D. (2003). Exterior differential systems and Euler-Lagrange partial differential equations. Univ. of Chicago Press.
Chicago Style (17th ed.) CitationBryant, Robert L., Phillip Griffiths, and Daniel Grossman. Exterior Differential Systems and Euler-Lagrange Partial Differential Equations. Chicago [u.a.]: Univ. of Chicago Press, 2003.
MLA (9th ed.) CitationBryant, Robert L., et al. Exterior Differential Systems and Euler-Lagrange Partial Differential Equations. Univ. of Chicago Press, 2003.
Warning: These citations may not always be 100% accurate.