You could use academic referencing style, e.g Harvard style "Mozilla (2021) Common Voice. Available at https://commonvoice.mozilla.org/ (Accessed: 15th September 2021)"
Fe allech chi ddefnyddio arddull cyfeirio Academaidd, e.e. arddull Harvard "Mozilla (2021) Common Voice. Ar gael yn https://commonvoice.mozilla.org/ (Cyrchwyd: 15fed Medi 2021)"