author = {Yann-Ga\"{e}l Gu\'{e}h\'{e}neuc and Herv\'{e} Albin-Amiot},
journal = cacm,instead of
journal = "Communications of the ACM",This allows you to uniformly abbreviate the journal titles, according to the publisher's style. For this to work, you'll need a list of journal abbreviations, like this or this one.
month = dec,instead of
month = "December",Again, this allows the style file to abbreviate month names only if required.
volume = 33, number = 6, year = 1990,instead of
volume = {33}, number = {6}, year = {1990},This is only a matter of style.
doi = {10.1145/78973.78974},instead of
doi = {http://doi.acm.org/10.1145/78973.78974},The resolver is not part of the DOI, and should not appear in it.