Gaia16apd – a link between fast and slowly declining type I superluminous supernovae by Kangas, T, Blagorodnova, N, Mattila, S, Lundqvist, P, Fraser, M, Burgaz, U, Cappellaro, E, Martínez, JM, Elias-Rosa, N, Hardy, LK, Harmanen, J, Hsiao, EY, Isern, J, Kankare, E, Kołaczkowski, Z, Nielsen, MB, Reynolds, TM, Rhodes, L, Somero, A, Stritzinger, MD, Wyrzykowski, Ł