What explains public transport use? Evidence from seven European cities by Gascon, M, Marquet, O, Gràcia-Lavedan, E, Ambròs, A, Götschi, T, Nazelle, ADE, Panis, LI, Gerike, R, Brand, C, Dons, E, Eriksson, U, Iacorossi, F, Ávila-Palència, I, Cole-Hunter, T, Nieuwenhuisjen, M