Volker Turau, Wolfgang Klas, & The Pennsylvania State University Cite Seer X Archives. (1992). Persistence in the Object-Oriented Database Programming Language VML. ftp://ftp.darmstadt.gmd.de/pub/oasys/reports/P-93-19.Ps.Z.
ISO-690 (author-date, English)VOLKER TURAU, WOLFGANG KLAS und THE PENNSYLVANIA STATE UNIVERSITY CITESEERX ARCHIVES, 1992. Persistence in the Object-Oriented Database Programming Language VML. ftp://ftp.darmstadt.gmd.de/pub/oasys/reports/P-93-19.ps.Z. 1 Januar 1992.
Modern Language Association 9th editionVolker Turau, Wolfgang Klas, und The Pennsylvania State University Cite Seer X Archives. „Persistence in the Object-Oriented Database Programming Language VML“. ftp://ftp.darmstadt.gmd.de/pub/oasys/reports/P-93-19.Ps.Z, Januar 1992.
Mohr Siebeck - Recht (Deutsch - Österreich)Volker Turau/Wolfgang Klas/The Pennsylvania State University Cite Seer X Archives: Persistence in the Object-Oriented Database Programming Language VML, ftp://ftp.darmstadt.gmd.de/pub/oasys/reports/P-93-19.ps.Z 1992,
Emerald - HarvardVolker Turau, Wolfgang Klas und The Pennsylvania State University Cite Seer X Archives. (1992), „Persistence in the Object-Oriented Database Programming Language VML“, ftp://ftp.darmstadt.gmd.de/pub/oasys/reports/P-93-19.Ps.Z.