Παραπομπή APA

Grassi, G. (1977). Union catalogue of printed books of the XV and XVI centuries in astronomical european observatories. Rome: [s.n.].

Παραπομπή Chicago Style

Grassi, Giovanna. Union Catalogue of Printed Books of the XV and XVI Centuries in Astronomical European Observatories. Rome: [s.n.], 1977.

Παραπομπή MLA

Grassi, Giovanna. Union Catalogue of Printed Books of the XV and XVI Centuries in Astronomical European Observatories. Rome: [s.n.], 1977.

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