- ISSN 1932-6203. PMC 8253445. PMID 34214114. Bjerke,
Ernst (13
December 2007). "Et "
tiaarigt Svangerskab"" [A
pregnancy of 10-years duration] (PDF).
Tidsskr Nor Laegeforen...
- (PDF).
Blyttia (in Norwegian). 66 (4): 235–243. Bjerke,
Ernst (2007). "Et «
tiaarigt svangerskab»" [A ten‑year pregnancy].
Tidsskrift for Den
norske legeforening...