The text in that PDF didn't show up correctly for me, but there's an HTML version of the paper here: https://www.cs.unm.edu/~crowley/papers/sds/sds.html https:

The text in that PDF didn't show up correctly for me, but there's an HTML version of the paper here: https://www.cs.unm.edu/~crowley/papers/sds/sds.html https://www.cs.unm.edu/~crowley/papers/sds/sds.html