Kilford, W. K. Elementary air survey (4th ed.).
Cita Chicago (17th ed.)Kilford, W. K. Elementary Air Survey. 4th ed.
Cita MLA (9th ed.)Kilford, W. K. Elementary Air Survey. 4th ed.
Atenció: Aquestes cites poden no estar 100% correctes.
Cita APA (7th ed.)