Something like
This version is based on data from the community project http://www.refugeephrasebook.de (12.09.2015). As we are working to improve the data, this handbook will be continually updated. All content can be copied, adapted and redistributed freely (Creative Commons License, CC0). Something to be changed/added? Please insert your suggestion at https://pad.okfn.org/p/rpb-suggestions , or contact us at feedback@refugeephrasebook.de . Thanks!
add some kind of license text and reference to http://www.refugeephrasebook.de/
Something like This version is based on data from the community project http://www.refugeephrasebook.de (12.09.2015). As we are working to improve the data, this handbook will be continually updated. All content can be copied, adapted and redistributed freely (Creative Commons License, CC0). Something to be changed/added? Please insert your suggestion at https://pad.okfn.org/p/rpb-suggestions , or contact us at feedback@refugeephrasebook.de . Thanks!
Source: https://en.wikibooks.org/wiki/Refugee_Phrasebook/Welcome_to_Austria,_Germany,_Switzerland