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Drivers for and barriers to the cross-border implementation of the once-only principleLeosk, Nele; Põder, Irma; Schmidt, Carsten; Kalvet, Tarmo; Krimmer, Robert JohannesThe once-only principle : The TOOP project2021 / p. 38–60 https://doi.org/10.1007/978-3-030-79851-2_3 Collection metrics at Scopus Article at Scopus Collection metrics at WOS Article at WOS

Exploring and demonstrating the once-only principle : a European perspectiveKrimmer, Robert Johannes; Kalvet, Tarmo; Toots, Maarja; Cepilovs, Aleksandrs; Tambouris, Efthimiosdg.o 2017 : the proceedings of the 18th Annual International Conference on Digital Government Research : Innovations and Transformations in Government : June 7-9, 2017, Staten Island, NY, USA2017 / p. 546-551 : ill https://doi.org/10.1145/3085228.3085235