Gathering Storm Magazine, Year 2, Issue 7Michael McHenry, Frank Coffman, Ron Collins, John Combs, Christina Grant, John Hawkhead, Timothy Hudenburg, Peter Hurtgen, Aaron Katzmarek, Frances Koziar · First published 2018Open the Tome
Handbook of technical instruction for wireless telegraphistsJohn Clayborough Hawkhead · First published 1914 · Latest edition 1915Open the Tome
