The Ancient Families of Dee and Day of Wales, England and Ireland. By George Edward Day and Leonard F. Day
History of the English Parliament: From the earliest times to the death of Charles II (2nd ed., 1894)
A Genealogical Register of the Descendants in the Male Line of Robert Day, of Hartford, Connecticut, Who Died in the Year 1648
A Practical Treatise on the Domestic Management and Most Important Diseases of Advanced Life. By George E. Day, M.D., F.R.S., Fellow of the Royal College of Physicians, and Professor of Medicine in the University of St Andrews
Report on the Institutions for the Deaf and Dumb in Central and Western Europe in the year 1844, to the Board of Directors of the New York Institution, by Rev. G. E. Day, Delegate of the Board, etc
A Genealogical Register of the Descendants in the Male Line of Robert Day, of Hartford, Conn., who Died in the Year 1648