In 1893 the Swedish actuary and mathematics historian Gustaf Eneström published a theorem on the complex roots of certain polynomials with real coefficients in a paper on pension insurance (in Swedish).
Sa 1893 ng Swedish actuary at matematika mananalaysay Gustaf Eneström-publish ng isang teorama sa komplikadong Pinagmulan ng mga tiyak na polynomials sa real coefficients sa isang papel sa pensiyon insurance (in Swedish).