Author,Title,Edition,Publisher,Year,Series,Number,ISBN,ISSN,URL "Ayres, Frank and Ault, John Clifford",Schaum's outline of theory and problems of differential equations in SI metric units,SI (metric) ed. / adapted by J.C. Ault,McGraw-Hill,1972,Schaum's outline series,,0070843961,,https://cir.nii.ac.jp/crid/1130000796616668416