Bijective proofs of Gould-Mohanty's and Raney-Mohanty's identities

Abstract: Using the model of words, we give bijective proofs of Gould-Mohanty's and Raney-Mohanty's identities, which are respectively multivariable generalizations of Gould's identity $$\sum_{k=0}^{{n}{x-kz\choose} k}{y+kz\choose n-k}= \sum_{k=0}^{{n}{x+\epsilon-kz\choose} k}{y-\epsilon+kz\choose n-k}$$ and Rothe's identity $$\sum_{k=0}^{{n}\frac{x}{x-kz}{x-kz\choose} k}{y+kz\choose n-k}= {x+y\choose n}.$$