SIMBAD references

Accurate astrometry is required to reliably cross-match 20th-century catalogues against 21st-century surveys. The present work aims to provide such astrometry for the 625 entries of the Bohannan & Epps (1974A&AS...18...47B; BE74) catalogue of Hα emission-line stars. BE74 targets have been individually identified in digital images and, in most cases, unambiguously matched to entries in the UCAC4 astrometric catalogue. Sub-arcsecond astrometry is now available for almost all BE74 stars. Several identification errors in the literature illustrate the perils of relying solely on positional coincidences using poorer-quality astrometry.