He apparently had no formal degree in architecture, yet applied for certification and became one of North Dakota's first licensed architects in 1917.
He later served as president of the North Dakota State Board of Architecture.
[1] A number of his works are listed on the U.S. National Register of Historic Places.
[2] Works include (with attribution as given in NRHP documents): According to the NRHP nomination, from 1989, for the Devils Lake Commercial District, the Dickey Free Library was designed by "John A. Shannon", late in his career.
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