Kreĭn, M.G.; Rutman, M.A. (1948). “Linear operators leaving invariant a cone in a Banach space” (Russian). Uspehi Matem. Nauk (N. S.)3 (1(23)): 1–95. MR0027128.. English translation: Kreĭn, M.G.; Rutman, M.A. (1950). “Linear operators leaving invariant a cone in a Banach space”. Amer. Math. Soc. Translation1950 (26). MR0038008.
Du, Y. (2006). “1. Krein–Rutman Theorem and the Principal Eigenvalue”. Order structure and topological methods in nonlinear partial differential equations. Series in Partial Differential Equations and Applications. 1. Maximum principles and applications. Hackensack, NJ: World Scientific Publishing Co. Pte. Ltd.. ISBN981-256-624-4. MR2205529
de Pagter, B. (1986). “Irreducible compact operators”. Math. Z.192 (1): 149–153. MR0835399.