J. Landmark

The Positive Triad of Schizophrenic Symptoms

E. Helmes, H. Merskey, Z. Cernovsky, 1990, British Journal of Psychiatry.

Inter‐Rater Reliability of Twelve Diagnostic Systems of Schizophrenia

E. Helmes, S. Kazarian, J. Landmark, 1983, The Journal of nervous and mental disease.

Subtypes of Schizophrenia: A Cluster Analytic Approach

E. Helmes, Edward Helmes, Jhan Landmark, 2003, Canadian journal of psychiatry. Revue canadienne de psychiatrie.