Credibility is related to Real. Real is a synonym of Genuine. 
Piece is related to Song. Song is related to Concert. you are likely to find Beer in/at/on Concert. you are likely to find Beer in/at/on Plane. 
Credibility <--RelatedTo--> Real <--Synonym--> Genuine 
Piece <--RelatedTo--> Song <--RelatedTo--> Concert <--AtLocation-- Beer --AtLocation--> Plane 