Abstract Composition 1963 Signed F. Fischer

Striking abstract work signed F. Fischer, numbered 36/100 and dated 1963.  We have been unable to determine the artist and would be grateful to hear from anyone who can help identify this work.
Possibilities include the Austrian Fritz FISCHER (1925-1986) or the German Fritz FISCHER (1889-1974), but we have not been able to see enough of their work to indicate that the style or signature are right.

40 x 50 cm including margins.