LIGGETT, John. Department of Psychological Medicine King's College University of Durham Queen Victoria Road Newcastle-Upon-Tyne, England. The Journal of Psychology. 1957-04, roč. 43, čís. 2, s. 225–237. Dostupné online [cit. 2020-08-01]. ISSN0022-3980. DOI10.1080/00223980.1957.9713068.
LIGGETT, John. Department of Psychological Medicine King's College University of Durham Queen Victoria Road Newcastle-Upon-Tyne, England. The Journal of Psychology. 1957-04, roč. 43, čís. 2, s. 225–237. Dostupné online [cit. 2020-08-01]. ISSN0022-3980. DOI10.1080/00223980.1957.9713068.
HORSLEY, JOHN, 1675-1732. Britannia Romana : or, The Roman antiquities of Britain. 2nd ed. [i.e. 1st ed. reprinted]. vyd. Newcastle upon Tyne: Graham vi, [5], xxxii, 560, [94] pages, [14] leaves s. Dostupné online. ISBN0-85983-090-X, ISBN978-0-85983-090-4. OCLC2965219