A HARPS-N mass for the elusive Kepler-37d: a case study in disentangling stellar activity and planetary signals by Rajpaul, VM, Buchhave, LA, Lacedelli, G, Rice, K, Mortier, A, Malavolta, L, Aigrain, S, Borsato, L, Mayo, AW, Charbonneau, D, Damasso, M, Dumusque, X, Ghedina, A, Latham, DW, López-Morales, M, Magazzù, A, Micela, G, Molinari, E, Pepe, F, Piotto, G, Poretti, E, Rowther, S, Sozzetti, A, Udry, S, Watson, CA