The First Organocatalysed Direct Aldol Reaction of 2-Hydroxycyclobutanone - Aitken, David J.; Capitta, Francesca; Frongia, Angelo; Gori, Didier; Guillot, Régis; Ollivier, Jean; Piras, Pier Paolo; Secci, Francesco; Spiga, Marco (Synlett, 2011)