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"Introitus" is a composition for piano and orchestra by the Russian composer Sofia Gubaidulina. The title, meaning "entrance" or "introduction" in Latin, suggests that the work serves as a gateway to a larger musical experience. Gubaidulina's unique musical language, characterized by its complex textures, intricate rhythms, and evocative harmonies, is fully on display in this piece, creating a captivating and immersive sound world for the listener.