Yep, that paper has been written, circa 1995. From Scicurious:
All the woodchucks ate the wood, none actively attempted to toss it, and none upchucked. They could, apparently digest the wood pretty well, and consumed it at a rate of 361.9237001 cubic centimeteres per animals per day
Of course this may be completely made up, and certainly involves some unethical animal testing … but science!