Multi-synaptic boutons are a feature of CA1 hippocampal connections in the stratum oriens by Rigby, M, Grillo, FW, Compans, B, Neves, G, Gallinaro, J, Nashashibi, S, Horton, S, Pereira Machado, PM, Carbajal, MA, Vizcay-Barrena, G, Levet, F, Sibarita, J-B, Kirkland, A, Fleck, RA, Clopath, C, Burrone, J