J. N. Ritchie

A report on artificial insemination in the United States submitted to the Agricultural Improvement Council.

J. Edwards, J. N. Ritchie, 1944 .

A Brief Review of those Animal Diseases for which Legislative Provision is made in Great Britain

J. N. Ritchie, 1953 .

Field Trials with B.C.G. for the Immunisation of Calves Against Tuberculosis

J. N. Ritchie, R. Glover, 1953 .

Neonatal death in Northern Ireland

J. N. Ritchie, G. Mcclure, S. Keilty, 1978, British medical journal.

Bovine Tuberculosis: the End in Sight

J. N. Ritchie, 1959, Royal Society of Health Journal.

Bovine tuberculosis.

J. N. Ritchie, 1948, Journal. Royal Sanitary Institute.