A precursor plateau and pre-maximum [O ii] emission in the superluminous SN2019szu: a pulsational pair-instability candidate. - Aamer, Aysha; Nicholl, Matt; Jerkstrand, Anders; Gomez, Sebastian; Oates, Samantha R; Smartt, Stephen J; Srivastav, Shubham; Leloudas, Giorgos; Anderson, Joseph P; Berger, Edo; de Boer, Thomas; Chambers, Kenneth; et al. (Monthly Notices of the Royal Astronomical Society, 2024)