Y Cwtta Cyfarwydd: 'the Chronicle Written by the Famous Clarke, Peter Roberts', for 1607-1646. With an Appendix From the Register Note-BoPeter RobertsVyprodánoPohlídat
The new Immigration; a Study of the Industrial and Social Life of Southeastern Europeans in AmericaPeter RobertsVyprodánoPohlídat
Anthracite Coal Communities: A Study of the Demography, the Social, Educational and Moral Life of the Anthracite RegionsPeter RobertsVyprodánoPohlídat