Why can't you just tell him? If you tell him and he doesn't understand, it's because he doesn't want to, because it would ruin HIS plans of having his children cared for so he can do whatever he wants. This is a selfish man, and you do not want him. If he doesn't care about your feelings and needs, a book with some other person's story isn't going to change him. Simply tell him no, you won't babysit. Period. Do you live together? Why? Move out. If you don't, problem solved. Be unavailable to show him you mean what you say.

why are his kids being dropped to you when he's at work?! doesnt that contradict the whole reason why they are there in the first place?
Not your kids, not your problem. Can they not go stay with his family??
to me he sound svery verys selfish. I have done this for 2 days only in the 2 yrs me and DH have lived together and that was purely becasue of family functions on my side we wnated them to attend.

Your free time should be skid freee otherwise you are going to end up resent them and mostly him! not good. tell him no, i dont remember giving birth to them so why am I stuck at home with them?

If you haven't told him how you feel yet, you need to .. NOW.

You need to lay down some serious boundaries.

And if you have already done this and he STILL takes advantage of you, I'm not sure giving him a book to read will help.

Absolutely, without a doubt read Stepmonster. I will save your sanity!