Fernanda B. Viégas Martin Wattenberg Matthew M. McKeon Frank van Ham Jesse Kriss Harry Potter and the Meat-Filled Freezer: A Case Study of Spontaneous Usage of Visualization Tools. 159 2008 conf/hicss/2008 HICSS http://doi.ieeecomputersociety.org/10.1109/HICSS.2008.188 db/conf/hicss/hicss2008.html#ViegasWMHK08