He has co-authored and co-edited several books such as "The International Human Rights Monitoring Mechanisms". De Zayas has published chapters in books "Ethnic Cleansing in Twentieth-Century Europe" co-edited by Steven Várdy and Hunt Tooley. In "International Humanitarian Law: Origins", edited by John Carey, de Zayas wrote the chapter "Ethnic Cleansing, Applicable Norms, Emerging Jurisprudence, Implementable Remedies". His chapter in Spanish "El crimen contra la paz" was published in the book "La Declaración de Luarca sobre el Derecho Humano a la Paz", edited by Carmen Rosa Rueda Castañón and Carlos Villán Durán.