Color-color diagram based on WISE magnitudes (in the Vega system), showing the positions of SMGs from H-ATLAS (in gray), and the elliptical galaxy selection (black box), defined by 0.5 < W2 − W3 < 1.5 and |W1 − W2|< 0.3 mag. The blue box corresponds to a sample of WISE-selected starburst galaxies used to test our fitting and cross-matching procedure. Confirmed lens candidates from the catalogs of Negrello et al. (2017) and Bakx et al. (2024) are shown as plus signs and crosses, respectively.