  A Sleeping Beauty is a publication that is apparently unrecognized for some
period of time before experiencing sudden recognition by citation. Various
reasons, including resistance to new ideas, have been attributed to such
delayed recognition. We examine this phenomenon in the special case of
co-citations, which represent new ideas generated through the combination of
existing ones. Using relatively stringent selection criteria derived from the
work of others, we analyze a very large dataset of over 940 million unique
co-cited article pairs, and identified 1,196 cases of delayed co-citations. We
further classify these 1,196 cases with respect to amplitude, rate of citation,
and disciplinary origin and discuss alternative approaches towards identifying
such instances.
