ON NONLINEAR EQUATIONS DELTAU+EU=O AND DV/DT=DELTAV+EV

[1] COURANT R, 1962, METHODS MATHEMATICAL, V2

[2] Gel'fand I.M., 1959, NAUK, V14, P87

[3] GelFand I., 1963, AM MATH SOC TRANSL 2, V29, P295

[4] A REMARK ON LINEAR ELLIPTIC DIFFERENTIAL EQUATIONS OF 2ND ORDER [J]. PROCEEDINGS OF THE AMERICAN MATHEMATICAL SOCIETY, 1952, 3 (05) : 791 - 793

[5] ON THE UPPER AND LOWER BOUNDS OF EIGENVALUES [J]. JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN, 1949, 4 (4-6) : 334 - 339

[1] COURANT R, 1962, METHODS MATHEMATICAL, V2

[2] Gel'fand I.M., 1959, NAUK, V14, P87

[3] GelFand I., 1963, AM MATH SOC TRANSL 2, V29, P295

[4] A REMARK ON LINEAR ELLIPTIC DIFFERENTIAL EQUATIONS OF 2ND ORDER [J]. PROCEEDINGS OF THE AMERICAN MATHEMATICAL SOCIETY, 1952, 3 (05) : 791 - 793

[5] ON THE UPPER AND LOWER BOUNDS OF EIGENVALUES [J]. JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN, 1949, 4 (4-6) : 334 - 339