Complex sentence: As an application to mathematical education, H. Jerome Keisler has written an elementary text on non-standard calculus that develops differential and integral calculus using the hyperreal numbers, which include infinitesimal elements.
Split into simpler sentences: As an application to mathematical education, H. Jerome Keisler wrote. Covering non-standard calculus, it develops differential and integral calculus using the hyperreal numbers, which include infinitesimal elements.