Master PJang and other friends, could you answer my questions?

Could anyone share me a sample of petition letter for NIW? Do the recommendation letters need to be sealed? I have a copy of old sample petition letters for EB-2. It lists something like section number such as I.N.A. §203(b)(2)(B)..Is it necessary to list these regulation or Act numbers? Can I just simply list of the criteria and say I meet some of them and meet the minimum requirement? If I have to refer to these regulations, where can I find it? Thank you very much.