Are hand jobs banned also? Not so sure on that one?
"Manual stimulation of a partner's genitals"? I think that's how they phrased it?
I seem to recall this was right out, too. For the same reason as oral & anal - because it is 'what homosexuals do' - specifically 'left the natural use of the female and became violently inflamed' blahblahblah.
Seriously. Since 'the natural use of the femle' is apparently limited to participating in missionary sex, everything else is banned - even within the marriage.
The major point is that 'lust' is wrong, even for your own spouse. Everything must be done with godly, chaste conduct in mind.