Do you have a citation for that? Wikipedia's history of complex numbers makes no mention of this. What uses for complex numbers did engineers have prior to Gaus

Do you have a citation for that? Wikipedia's history of complex numbers makes no mention of this. What uses for complex numbers did engineers have prior to Gauss that weren't anticipated by mathematicians? https://en.m.wikipedia.org/wiki/Complex_number#History https://en.m.wikipedia.org/wiki/Complex_number#History