  We derive a simple formula relating the cross section for light cluster
production (defined via a coalescence factor) to the two-proton correlation
function measured in heavy-ion collisions. The formula generalises earlier
coalescence-correlation relations found by Scheibl & Heinz and by Mrowczynski
for Gaussian source models. It motivates joint experimental analyses of Hanbury
Brown-Twiss (HBT) and cluster yield measurements in existing and future data
sets.
