“…It involved the participation of several coworkers from Sweden and abroad, who all made important contributions to our joint projects. Some of our results were also presented at various meetings, and gave rise to highly stimulating discussions [13][14][15][16][17][18].As indicated by the titles of our publications, these related to various "hot topics" in those days' bioenergetics, such as the reversibility of oxidative phosphorylation [1,2,7,10,11,[13][14][15][16][17][18], the compartmentation of ATP derived from substrate-level phosphorylation in relation to that generated by respiration [3,5,6], the use of rotenone as a specific inhibitor of Complex I of the respiratory chain [8,9], the utilization of energy from the respiratory chain in the absence of the phosphorylating system [12], and the biochemical characterization of human skeletal muscle mitochondria [4], an important tool for the study of mitochondrial diseases [19][20][21][22][23]. Licio's contribution has been pivotal in pursuing these projects, and his deep personal engagement created a warm atmosphere not only among his collaborators but in our laboratory as a whole.After these years of collaboration, Licio and I maintained active contact.…”