where is automatic transmission fluid filler? on 1993 BMW 325is

i want to add an additive to automatic transmission on 1993 bmw 325is. i cannot find where to add liquid.

Asked by for the 1993 BMW 325is
On your vehicle, there is no Dipstick, if your transmission is leaking fluid, you may want to get that inspected.
If you need this diagnosed properly you can call one of our four stores @
1) Willowbrook (281) 890-9400 3) The Woodlands (281) 465-9410
2) Champions (281) 370-7900 4) Cypress (281) 304-7833