The DBL Survey I: discovery of 34 double-lined double white dwarf binaries. - Munday, James; Pelisoli, Ingrid; Tremblay, P -E; Marsh, T R; Nelemans, Gijs; Bédard, Antoine; Toonen, Silvia; Breedt, Elmé; Cunningham, Tim; O'Brien, Mairi W; Dawson, Harry (Monthly Notices of the Royal Astronomical Society, 2024)