@article{239917,
 author = {Andrew K. Wright and Robert Cartwright},
 title = {A practical soft type system for scheme},
 journal = {ACM Transactions on Programming Languages and Systems (TOPLAS)},
 volume = {19},
 number = {1},
 year = {1997},
 issn = {0164-0925},
 pages = {87--152},
 doi = {http://doi.acm.org/10.1145/239912.239917},
 publisher = {ACM Press},
 }