ETGEN, G. J. (1977). An Introduction to ordinary differential: Equations with difference equations, numerical methods and applications. Harper and Row.
Chicago-čujuhus (17. p.)ETGEN, Garret J. An Introduction to Ordinary Differential: Equations with Difference Equations, Numerical Methods and Applications. New York: Harper and Row, 1977.
MLA-čujuhus (9. p.)ETGEN, Garret J. An Introduction to Ordinary Differential: Equations with Difference Equations, Numerical Methods and Applications. Harper and Row, 1977.
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