-* Figure out why the tests for section (2.8),
- e.g. prop_c3000_identity, are affected by switching two vertices of
- a tetrahedron.
+* Add the section (2.9) tests.
+
+* Figure out why the section (2.5) c_ijk1 identity is failing.
+
+* Use distribution combinators[1] to get rid of the orphan instance
+ warnings.
+
+* Update show definitions.
+
+[1] http://stackoverflow.com/questions/4001861/how-small-should-i-make-make-modules-in-haskell