APA (7th ed.) Citation

Stubbe, J. (2026). Sum rules and a second order Feynman-Hellman theorem for abstract operators with applications.

Chicago Style (17th ed.) Citation

Stubbe, Joachim. Sum Rules and a Second Order Feynman-Hellman Theorem for Abstract Operators with Applications. 2026.

MLA (9th ed.) Citation

Stubbe, Joachim. Sum Rules and a Second Order Feynman-Hellman Theorem for Abstract Operators with Applications. 2026.

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