Word Ladders is part of the Abstraction project, funded by the European Commission. Abstraction is a 5-year project funded by the European Research Council (grant agreement: erc-2021-stg-101039777), led by Marianna Bolognesi, phd, at the University of Bologna, Italy. The intellectual property of the Word Ladders game belongs to the University of Bologna (Italy). 

Word Ladders therefore is funded by the European Union. Views and opinions expressed are, however, those of the author(s) only and do not necessarily reflect those of the European Union or the European Research Council. Neither the European Union nor the granting authority can be held responsible for them. 

For the realization of the mobile application Word Ladders, we are thankful to Margherita Bolognesi, Francesca Strik Lievers and Nate Laffan for their ideas and feedback on the concept of the game. We are also thankful to Francesca Genovese and Andrea Ferrari for the development of the prototype, and to Synesthesia for its improvement and publication in the online app stores. 

We are thankful to Tommaso Bolognesi for developing the catchy soundtrack of the game (turn up the volume if you have not listened to it yet!) 

We are also thankful to the developers of WordNet, the lexical database hosted by Princeton University, U.S.A., for making available for research their tools, and the developers of MultiWordNet, the multilingual lexical database in which the Italian WordNet is strictly aligned with Princeton WordNet 1.6. MultiWordnet is hosted by FBK Foundation in Trento, Italy. 

The Word Ladders app uses MultiWordNet 1.5.0, for a partial evaluation of the data produced by users within the game. MultiWordNet is licensed under a Creative Commons Attribution 3.0 Unported License.