Low-resolution optical spectra for 38 candidates confirmed as M and L subdwarfs (black) with their identifier (ID) and telescope name. Overplotted in red are subdwarf spectral templates from SDSS used to assign the final spectral types (see Sect. 5.2). Candidates with ID = 1, 8, and 83 appear twice, because they have spectra from our own follow-up and from the SDSS spectroscopic database.