Canon Speedlite 470EX-AI External Flash 1957C002 - Best Buy
Canon EL-100 Flash Review by Ken Rockwell
Canon Speedlite 188A Shoe Mount Flash - Etsy Norway
Amazon.com : GODOX TT685II-C Flash for Canon Speedlight Camera Flash E-TTL Speedlite High-Speed Sync, 2.4G Wireless X System Compatible for Canon Flash 5D Mark IV 6D Mark II 7D 90D 250D R5
Canon Speedlite 430EX flash: Digital Photography Review