A great classic, the Gift by Marcel Mauss:https://en.wikipedia.org/wiki/The_Gift_(book)
With free PDFs available online. It starts with a old Scandinavian poem:
"I have never found a man so generous and hospitable that he would not receive a present, nor one so liberal with his money that he would dislike a reward if he could get one.
Friends should rejoice each others’ hearts with gifts of weapons and raiment, that is clear from one’s own experience. That friendship lasts longest—if there is a chance of its being a success—in which friends both give and receive gifts._
A man ought to be a friend to his friend and repay gift with gift. People should meet smiles with smiles and lies with treachery.
Know—if you have a friend in whom you have sure confidence and wish to make use of him, you ought to exchange ideas and gifts with him and go to see him often.
If you have another in whom you have no confidence and yet will make use of him, you ought to address him with fair words but crafty heart and repay treachery with lies.
Further, with regard to him in whom you have no confidence and of whose motives you are suspicious, you ought to smile upon him and dissemble your feelings. Gifts ought to be repaid in like coin.
Generous and bold men have the best time in life and never foster troubles. But the coward is apprehensive of everything and a miser is always groaning over his gifts.
Better there should be no prayer than excessive offering; a gift always looks for recompense. Better there should be no sacrifice than an excessive slaughter."
Havamal, vv. 39, 41-2, 44-6, 48 and 145, from the translation by D. E. Martin Clarke in The Havamal, with Selections from other Poems in the Edda, Cambridge, 1923.