@article{diagrams,
author = {Smith, Glenn G. and Ferguson, David},
doi = {10.1080/0020739042000232583},
issn = {0020-739X},
journal = {International Journal of Mathematical Education in Science and Technology},
number = {5},
pages = {681+},
publisher = {Taylor and Francis Ltd},
title = {{Diagrams and math notation in e-learning: growing pains of a new generation}},
url = {http://dx.doi.org/10.1080/0020739042000232583},
year = {2003},
volume = {35}
}
$$
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$$