Ah ok
"Proprioception(?), sensitivity to touch, develops from 8 weeks GA and by 32 weeks GA most of the body is sensitive to the light stroke of a feather [20]."
Seems kind of like a range to me.... Tried to click on the source of your source [20] for more details and it was in Japanese. ¿
Your source more clearly claims responses to sound at 16 weeks..which is still not 20 somethin weeks but compared to a grown adult that difference seems a bit trivial.
But ya anyways I read something (I think out of the UK) that said different. Now of course I can't find it so you probably think I'm lying. eh..