Obtain the most recent author from a high impact journal that has the specific information you require. But don't ignore classic papers that first described the effect either :)

Dear Soongull Aziz

I agree with Andrew Paul McKenzie Pegman

However, all of them can be inserted if they come from classy Journals. Papers older than 2000 should not be used if applicable.

Thanks.

Aydin Mesgar papers older than 2000 definitely should be used. I don’t know why you write that