If I were you, I would use this approach:
NSMutableArray *allPhoneNumbers = @[].mutableCopy;
NSArray *allContact = (__bridge NSArray*)ABAddressBookCopyArrayOfAllPeople(book);
for (id rec in allContacts){
ABMultiValueRef mvr = ABRecordCopyValue((__bridge ABRecordRef)rec, kABPersonPhoneProperty);
NSArray *currentNums = (__bridge NSArray*) ABMultiValueCopyArrayOfAllValues(mvr);
[allPhoneNumbers addObjectsFromArray: currentNums];
}
I have not tested this, but it should work. Tell me if you have any issues.
If you want just one contact's numbers (the above gets every contact), use this code.
ABMultiValueRef mvr = ABRecordCopyValue(yourRecordRef, kABPersonPhoneProperty);
NSArray *currentNums = (__bridge NSArray*) ABMultiValueCopyArrayOfAllValues(mvr);
[allPhoneNumbers addObjectsFromArray: currentNums];