How to turn this formula into CNF?

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This formula

$$(p \land q) \lor ( \neg q \lor r) \land ( \neg p \lor r)$$

has the CNF

$$(\neg p \lor q \lor r) \land ( p \lor \neg q \lor r)$$

I understand how CNF works, but I can't seem to figure out my next steps from the above formula. I tried to carrying out distribution. Didn't work. Could anyone suggest a way to get to that CNF expression?