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In popular culture, is a recognized title for modern thrillers and series:

The work creates a "poet-combatant" alter ego who reflects on the duality of being an artist while enduring the brutality of trench warfare. Cinematic and Contemporary Media

In the context of historical and war literature, the term is frequently linked to the collection (The Unknown Soldier) by the Nicaraguan poet Salomón de la Selva .

Are you writing an essay about the of the "unknown" or "stranger"? Pessoa, Unknown to Paz - Project MUSE

Published in 1922, it is often cited as the only major book of First World War poetry written in Spanish.