Famous texts which Forsyth published before his 1893 work Theory of Functions of a complex variable, are A treatise on differential equations (1885), and Theory of differential equations published in six volumes between 1890 and 1906.
Bantog na teksto na inilathala bago ang kanyang Forsyth 1893 trabaho teorya ng pag-andar ng isang kumplikadong variable, ay isang treatise sa kaugalian equation (1885), at teorya ng kaugalian equation na nai-publish sa anim na volume na sa pagitan ng 1890 at 1906.