Report of the Committee appointed by the Tax Conference of Pennsylvania Interests to examine the Tax Laws of the American States.;Valuation, Taxation and Exemption in the Commonwealth of Pennsylvania.;Report of the Tax Commission of Ohio.;The Injustice and Inexpediency of Double Taxation.by George C. Crocker;Double Taxation Unjust and Inexpedient.by Richard H. Dana;Hearings before the [Massachusetts] Joint Special Committee on Taxation.