APA (7th ed.) Citation

Heil, E. (1974). Eigenvalue estimates for Hill's equation. Techn. Hochsch.

Chicago Style (17th ed.) Citation

Heil, Erhard. Eigenvalue Estimates for Hill's Equation. Darmstadt: Techn. Hochsch, 1974.

MLA (9th ed.) Citation

Heil, Erhard. Eigenvalue Estimates for Hill's Equation. Techn. Hochsch, 1974.

Warning: These citations may not always be 100% accurate.