Rules Question

[holdem17]

I have a question about a rule, I'd like to know what people think about it.
I'm playing NLH at Absolute Poker, SB 0.25, BB 0.25, buy in 100.
After the flop Player A raises 6.50, I call, and Player B has a 6.60 stack and goes all in, effectively raising only 10 cents.
Now on the same betting round (the flop) Player A was allowed to re-raise, and he raised 13.70 more
I remember reading somewhere that this is not allowed, as the minimum raise to re-open the bets is the original bet size
Do you agree that the minimum raise to re-open is the bet size?
Does anybody have a link to a poker rule that explains this?
TIA & Regards ...