Can you help me with some references to public libraries accepting corporate donations and guidelines for acknowledging the donations?

Here in Sacramento, CA, the Sacramento Public Library accepted computers for a branch library from the local professional basketball NBA teams. In turn, the library allowed what amounts to excessive brazen advertisement in the building for the teams. (I won't go into it at length here, but it really is.) SPL administrators dismiss concerns and focus on the usefulness of the computers, but admit they have no guidelines.

Isn't there some discussion somewhere about corporate intrusion into public libraries? The Internet is replete with ways to raise money for libraries, including from corporations, but I can't find any reference to policies and guidelines for accepting corporate largesse.

I would very much appreciate any help you can provide.