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For copyright purposes, a work, such as a periodical, anthology or encyclopedia, in which a number of separate and independent works are assembled into one work. To create a collective work, permission must be obtained from the owners of the copyrights of the constituent parts (assuming such parts are not already in the public domain). Although the author of the compilation may not own the copyright to any of the individual parts, the creativity involved in selecting and organizing the constituent materials is in itself protected by copyright.