Goorbergh, E. v. d., Zweerman, T. H., Saggau, E., & Sansone, P. (2001). Respectfully yours, signed and sealed, Francis of Assisi: Aspects of his authorship and focuses of his spirituality. Franciscan Institute.

Goorbergh, Edith van den, Th. H. Zweerman, Elise Saggau, agus Paul Sansone. Respectfully Yours, Signed and Sealed, Francis of Assisi: Aspects of His Authorship and Focuses of His Spirituality. St. Bonaventure, New York: Franciscan Institute, 2001.

Goorbergh, Edith van den, et al. Respectfully Yours, Signed and Sealed, Francis of Assisi: Aspects of His Authorship and Focuses of His Spirituality. Franciscan Institute, 2001.