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Visible, less visible, and invisible work: Patterns of collaboration in 20th century chemistry

We chronicle the use of acknowledgments in 20th century chemistry by analyzing and classifying over 2,000 specimens covering a 100-year period. Our results show that acknowledgment has gradually established itself as a constitutive element of academic writing--one that provides a revealing insight into the structural nature of subauthorship collaboration in science. Complementary data on rates of coauthorship are also presented to highlight the growing importance of teamwork and the increasing division of labor in contemporary chemistry. The results of this study are compared with the findings of a parallel study of collaboration in both the social sciences and the humanities.