The exhibition Contra o Muro constitutes the first important group of paintings presented to the Portuguese public by Dumas and a new step in her oeuvre. A challenging and concerned body of work, Dumas has concentrated for the first time on painting architectural constructions in this case the 'security wall' between Israel and Palestine, its violence and human tragedy. Paintings, texts and found media emphasise the social reality of segregation, oppression and domination. But these new works also transform into general explorations of death, loss and sacrifice, in a groundbreaking statement for Dumas that is simultaneously political, self-questioning and poetic.
Various is the correct author for any book with multiple unknown authors, and is acceptable for books with multiple known authors, especially if not all are known or the list is very long (over 50).
If an editor is known, however, Various is not necessary. List the name of the editor as the primary author (with role "editor"). Contributing authors' names follow it.
Note: WorldCat is an excellent resource for finding author information and contents of anthologies.