Many studies of the Norvegian (0rthodox Christian) Liturgist Stig Simeon R. Froyshov are available here :
http://www.mhzh.ru/en/author/91/Frøyshov
here:
https://www.academia.edu/4874642/Greek_Hymnody
and here:
https://uio.academia.edu/StigSimeonFrøyshov
Most of them can be downleaded.
http://www.mhzh.ru/en/author/91/Frøyshov
here:
https://www.academia.edu/4874642/Greek_Hymnody
and here:
https://uio.academia.edu/StigSimeonFrøyshov
Most of them can be downleaded.