References

Aleksander and Morton, 1990

Aleksander, I. and Morton, H. (1990). Neural Computing. Chapman hall.
Quite good on Hopfield nets and contains a similar example to the one given in these notes.

Hopfield, 1982

Hopfield, J. (1982). Neural networks and physical systems with emergent collective computational properties. Proceedings of the National Academy of Sciences of the USA, 79:2554 - 2588. Hopfield has another, related, model which uses continuous outputs. Beware when reading the literature which model is being discussed.

McEliece et al., 1987

McEliece, R., Posner, E., Rodemich, E., and Venkatesh, S. (1987). The capacity of the hopfield associative memory. IEEE Transactions on Information Theory, IT-33:461 - 482.
There are many papers on this area, but this has some non- technical material near the beginning before getting into the welter of maths needed for this kind of analysis.