<review>The entry is very good. I only have two minor suggestions.
First, Pontryagin and his students developed their celebrated maximum principle in the late 50's. If I remember correctly the original book was published in 1958 (in Russian).
Second, the key point in the mathematical theory of optimal control is the existence of the Lagrange multiplier function \lambda(t). The entry introduces it in an intuitive way which is nice for the average readers, but a brief mention of the this point might be useful. For example citing the treatment in
D. G. Luenberger, Optimization by Vector Space Methods, John Wiley & Sons, Inc., 1997
might be useful for more mathematically oriented readers.</review>
Response to Reviewer B
Thank you for your valuable comments. I agree with your suggestions and have made minor changes to the article accordingly.
Victor M. Becerra