Gear C. Numerical Initial Value Problems in Ordinary Differential Equations 1971

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The successful solution of a realistic problem in applied mathematics requires the fusion of four distinct ingredients: (1) knowledge of the subject area of the problem; (2) knowledge of the relevant mathematics; (3) knowledge of the relevant computer science; (4) a talent for selecting just what part of all this knowledge will actually solve the problem, and ignoring the rest.
Professor Gear is one of those rare individuals with these four capabilities. He has made himself familiar with subject areas that spawn differential equations. He has a good grounding in mathematical analysis. He has demonstrated a capacity as a systems programmer and teacher of systems programming, and is as capable in symbol manipulation as he is in computing with numbers. He has created powerful programs (e.g., DIFSUB on pp. 158-166) for solving difficult practical problems. In particular, he knows a lot about solving stiff differential equations, a difficult area that has received much attention in recent years