see: supersede Usage: Supercede has occurred as a spelling variant of supersede since the 17th century, and it is common in current published writing. It continues, however, to be widely regarded as an error.
SUPERCEDE
Meaning of SUPERCEDE in English
Merriam Webster. Explanatory English dictionary Merriam Webster. Толковый словарь английского языка Мерриам-Уэбстер. 2012