de Snoo, H., & Woracek, H. (2018). Compressed resolvents, Q-functions and h0-resolvents in almost Pontryagin spaces. In Indefinite Inner Product Spaces, Schur Analysis, and Differential Equations (Vol. 264, pp. 425–484). Birkhäuser. https://doi.org/10.1007/978-3-319-68849-7_18