Papers

  • Valentin Goranko, Ruaan Kellerman, and Alberto Zanardo, Structural Theory of Trees. II. Completeness and Completions of Trees, to appear in Contributions to Discrete Mathematics

  • Valentin Goranko, Ruaan Kellerman, and Alberto Zanardo, Structural Theory of Trees. I. Branching and Condensations of Trees, to appear in Contributions to Discrete Mathematics

  • Ruaan Kellerman, First-order theories of bounded trees, Archive for Mathematical Logic, vol. 61 issue 1 - 2, pp. 263 - 297, 2022

  • Valentin Goranko and Ruaan Kellerman, Approximating trees as coloured linear orders and complete axiomatisations of some classes of trees, Journal of Symbolic Logic, vol. 86 no. 3, pp. 1035 - 1065, 2021

  • Ruaan Kellerman, First-order aspects of tree paths, Logic Journal of the IGPL, vol. 24 no. 4, pp. 688 - 704, 2015

  • Valentin Goranko and Ruaan Kellerman, Classes and theories of trees associated with a class of linear orders, Logic Journal of the IGPL, vol. 19 no. 1, pp. 217 - 232, 2011

  • Ruaan Kellerman, First-Order Theories of Orthogonality Structures, Logic Journal of the IGPL, vol. 15 no. 3, pp. 255 - 270, 2007

Book chapters

  • Philippe Balbiani, Valentin Goranko, Ruaan Kellerman and Dimiter Vakarelov, Logical Theories for Fragments of Elementary Geometry, Handbook of Spatial Logics, pp. 343 - 428, Springer, 2007

Activities

  • 64th Annual Congress of the South African Mathematical Society, Bloemfontein, South Africa, 29 November - 1 December 2021 (held online)

  • Logic Colloquium 2021 (2021 European Summer Meeting of the Association for Symbolic Logic), Poznań, Poland, 19 - 24 July 2021 (held online)

  • UJ Logic Workshop, Johannesburg, South Africa, 27 - 28 January 2020

  • Research visit to Valentin Goranko at Stockholm University, Sweden, 3 - 27 April 2018

  • UJ Logic Workshop, Johannesburg, South Africa, 29 - 30 January 2018

  • 58th Annual Congress of the South African Mathematical Society, Johannesburg, South Africa, 4 - 6 November 2015

  • Model Theory Conference, Stellenbosch, South Africa, 9 - 13 March 2015

  • Research visit to Valentin Goranko at the Danish Technical University, Denmark, 8 - 31 August 2013

  • 8th Scandinavian Logic Symposium, Roskilde, Denmark, 20 - 21 August 2012

  • 53rd Annual Congress of the South African Mathematical Society, Pretoria, South Africa, 3 - 5 November 2010

  • Zuse-Collatz Colloquium, Pretoria, South Africa, 9 October 2010

  • 52nd Annual Congress of the South African Mathematical Society, Johannesburg, South Africa, 2 - 4 November 2009

  • 7th Panhellenic Logic Symposium, Patras, Greece, 15 - 19 July 2009

  • Logic Colloquium 2006 (2006 European Summer Meeting of the Association for Symbolic Logic), Nijmegen, The Netherlands, 27 July - 2 August 2006

  • 1st World School on Universal Logic, Montreux, Switzerland, 26 - 30 March 2005

Refereeing

I have reviewed manuscripts for the following journals:

  • Quaestiones Mathematicae

  • Journal of Logic, Language and Information

DAL Seminar Series

I coordinate the seminar series in Discrete Mathematics, Algebra, and Logic (DAL) at the University of Pretoria. Please contact me if you are interested in giving a talk as part of this series.