• Contributing to a digital single market for Europe: barriers and drivers of an EU-wide once-only principleKalvet, Tarmo; Toots, Maarja; Krimmer, Robert Johannesdg.o 18 : Proceedings of the 19th Annual International Conference on Digital Government Research : Governance in the Data Age : Delft, Netherlands, May 30-June 01, 20182018 / Article No. 45, 8 p https://doi.org/10.1145/3209281.3209344 https://www.scopus.com/sourceid/11600154611 https://www.scopus.com/record/display.uri?eid=2-s2.0-85049025992&origin=inward&txGid=06935f6348e8112cf7e261e62412b7fa https://www.webofscience.com/wos/woscc/full-record/WOS:000511427500045
• Cross-border e-government services in Europe: expected benefits, barriers and drivers of the once-only principleKalvet, Tarmo; Toots, Maarja; Veenstra, Anne Fleur van; Krimmer, Robert JohannesICEGOV2018 : proceedings of the 11th International Conference on Theory and Practice of Electronic Governance : 4 - 6 April 2018, Galway, Ireland2018 / p. 59-68 https://doi.org/10.1145/3209415.3209458 https://www.scopus.com/sourceid/11600154611 https://www.scopus.com/record/display.uri?eid=2-s2.0-85051439288&origin=inward&txGid=2e3e4f81ae1a75971035f2726fae5e43 https://www.webofscience.com/wos/woscc/full-record/WOS:000515826000010
• 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 https://www.scopus.com/sourceid/11600154611 https://www.scopus.com/record/display.uri?eid=2-s2.0-85023608403&origin=inward&txGid=921275c0243ae7b6b277dc76de8ba0f1 https://www.webofscience.com/wos/woscc/full-record/WOS:000644436100062
• How to implement the European digital single market : identifying the catalyst for digital transformationSchmidt, Carsten; Krimmer, Robert JohannesJournal of European Integration2022 / 21 p. : ill https://doi.org/10.1080/07036337.2021.2011267 https://www.scopus.com/sourceid/5700162364 https://www.scopus.com/record/display.uri?eid=2-s2.0-85124370454&origin=inward&txGid=45dc72864f368b0239a04a8f0e882a2a https://jcr.clarivate.com/jcr-jp/journal-profile?journal=J%20EUR%20INTEGR&year=2022 https://www.webofscience.com/wos/woscc/full-record/WOS:000752619900004
• Once only principle : benefits, barriers and next stepsWimmer, Maria A.; Tambouris, Efthimios; Krimmer, Robert Johannes; Gil-Garcia, J. Ramon; Chatfield, Akemi Takeokadg.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. 602-603 : ill https://doi.org/10.1145/3085228.3085296 https://www.scopus.com/sourceid/11600154611 https://www.scopus.com/record/display.uri?eid=2-s2.0-85023596754&origin=inward&txGid=98eeacf70a6be1c2e16ce07e87c46b8f https://www.webofscience.com/wos/woscc/full-record/WOS:000644436100083
• Towards a Cross-Border Reference Architecture for the Once-Only Principle in Europe : An Enterprise Modelling ApproachTepandi, Jaak; Grandry, Eric; Fieten, Sander; Draheim, Dirk; Piho, GunnarThe Practice of Enterprise Modeling : 12th IFIP Working Conference, PoEM 2019,Luxembourg, Luxembourg, November 27–29, 2019 : proceedings2019 / p. 103-117 https://doi.org/10.1007/978-3-030-35151-9_7 https://www.scopus.com/sourceid/17500155101 https://www.scopus.com/record/display.uri?eid=2-s2.0-85076686559&origin=inward&txGid=3aac6a2233d72e9b29b0fb4e59c7f34c https://www.webofscience.com/wos/woscc/full-record/WOS:000611409100007
• “When need becomes necessity” - The single digital gateway regulation and the once-only principle from a European point of view
  Schmidt, Carsten; Krimmer, Robert Johannes; Lampoltshammer, Thomas J.Open Identity Summit 2021: Fachtagung vom 01.-02. Juni 2021 Copenhagen2021 / p. 223-228 https://dl.gi.de/server/api/core/bitstreams/ec03538d-b376-4537-bc0f-aab2936c74f8/content https://www.scopus.com/sourceid/21100229106 https://www.scopus.com/record/display.uri?eid=2-s2.0-85120520994&origin=resultslist&sort=plf-f&src=s&sid=b0dcfb58993e0eeceaf7e845ac02712b&sot=b&sdt=b&s=TITLE-ABS-KEY%28%22%22When+need+becomes+necessity%22+-+The+single+digital+gateway+regulation+and+the+once-only+principle+from+a+European+point+of+view%22%29&sl=144&sessionSearchId=b0dcfb58993e0eeceaf7e845ac02712b&relpos=0