In bin-packing, the difficulty of the problem comes from the fact that the items are different sizes. In any casting of the OP problem in terms of bin packing, you would have all items the same size, which completely trivializes the problem. Also, in any bin-packing problem there is generally an unlimited supply of bins of fixed capacity, unlike in the OP where there are a fixed number of bins with unlimited capacity. Any references on bin packing (let alone TSP, which seems completely unrelated apart from it also being NP-complete, or knapsack, in which items have both a variable cost and variable weight) will be unlikely to have anything relevant for these variants (let alone the very specific problem of enumerating solutions).