Literature references

2 literature references:

Author: Rothmaler W. & al.
Year: 1988
Title:
Source: Exkursionsflora fur die Gebiete der DDR und der BRD. Bd.2.
Author: Rothmaler,W. et al.
Year: 1982
Title:
Source: Exkursionsflora fur DDR...und BRD. Volk, Berlin