First-Order Nonlinear Equations with Three or More Independent Variables
2011 ◽
pp. 125-174
1958 ◽
Vol 10
◽
pp. 127-160
◽
2011 ◽
Vol 25
(14)
◽
pp. 1931-1939
◽
1966 ◽
Vol 6
(5)
◽
pp. 136-151
◽
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