Schubert, W. (1950). Sybellus for evangelism. General Conferencia of S.D.A.
Cita Chicago (17th ed.)Schubert, Walter. Sybellus for Evangelism. General Conferencia of S.D.A, 1950.
Cita MLA (9th ed.)Schubert, Walter. Sybellus for Evangelism. General Conferencia of S.D.A, 1950.
Atenció: Aquestes cites poden no estar 100% correctes.