Reference field problem (can any one help me with this issue)

i need to give my purchase manager the access to link contact and addresses to suppliers but i can’t find the specific role to give her in order to unlock link (reference) to supplier field except for system manager and to be honest i can’t give her system manager role in order to fix this issue is there any advice for me in order to fix this issue also i will attach screen shoot from her user shows what kind of problem she faces whenever she try to link contact or address to supplier.