after the don gets shot and sonny finds out it was because of paulie gatto...he has clemenza against the wall and says something along the lines of...

sonny: i want paulie gatto here right away
clemenza: he's home sick today
sonny: i dont care, i want him here, IF HE'S BREATHING, i want him here

also when de niro in 2 says somethin like...

i dont get it, there's 3 of us and one of him (about fanucci)

"never rat on your friends, and always keep your mouth shut"
-jimmy conway

"like that..POOF..he's gone"
-verbal kint