The linguistic findings showing that American Sign Language (ASL) is a true and natural language were published by William Stokoe.

He was an English professor at Gallaudet University whose 1960 paper Sign Language Structure analyzed ASL’s grammar and demonstrated that it has its own phonology, morphology, and syntax, just like spoken languages. His work is widely credited with revolutionizing how scholars and educators view ASL and with helping establish it as a fully recognized natural language in its own right.

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