@article{baecker,
author = {Baecker, Ronald M.},
title = {TIMELINES
Themes in the early history of HCI---some unanswered questions},
journal = {interactions},
volume = {15},
number = {2},
year = {2008},
issn = {1072-5520},
pages = {22--27},
doi = {http://doi.acm.org/10.1145/1340961.1340968},
publisher = {ACM},
address = {New York, NY, USA},
}
$$
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$$