Information on Hadelandís freelance designers is unfortunately sketchy. Most of those hired to do decorative work were sculptors, like Fletre. The glass design was more of a sideline not given much attention by art historians, for whom itís all about the sculptures.
Speaking Norwegian doesnít help much either, as there is little to be found about Fletreís glass designs anywhere here. Even the Norwegian Artists Encyclopedia offers little.
During his first ten years in the US, Fletre received an extensive artistís training in Chicago, before returning to Norway in 1933. He worked for Hadeland 1941-50, creating designs for the new sandblasting and deep etching techniques being developed there by the pioneering StŚle Kyllingstad. Some of Fletreís designs became quite popular, and remained in the catalogue long after his departure from Hadeland. After returning to Chicago in 1954, he only visited Norway briefly. He died in Oslo, however, having come there to work on a commision for a sculpture.
I have a couple of his pieces. They are not expensive; a first class FLC vase would set you back $200 at most.