Über mehrdeutige flächentransformationen,

Mode of access: Internet.

Publications de l'Observatoire astronomique Engelhardt de l'Universite de Kasan.

Mode of access: Internet.

Meddelande från Lunds astronomiska observatorium. Serie II.

Each no. has also a distinctive title.

SGU series Ca. Research papers = SGU series Ca. Forskningsrapporter.

Mode of access: Internet.

Ueber einige kalktuffe aus Westergötland.

Thesis (Ph.D.)--Upsala university.