References
- Buck , R. C. 1965 . Advanced Calculus
- Cesari , L. 1982 . Optimization-Theory and Applications Problems with Ordinary Differential Equations , New York : Springer-Verlag . Appl. Math.
- Edwards , R. E. 1965 . Functional Analysis: Theory and Applications , New York : Holt, Rinehart and Winston .
- McShane , E. J. 1944 . Integration , Princeton : Princeton Univ. Press .
- Tonelli , L. 1923 . Fondamenti di Calcolo delle Variazioni , Vol. 2 , Bologna : Zanichelli .