• Effect of chemical modification of wood flour on the mechanical properties of wood-plastic compositesKallakas, Heikko; Shamim, M. A.; Olutubo, T.; Poltimäe, Triinu; Süld, Tiia-Maaja; Krumme, Andres; Kers, JaanAgronomy research2015 / p. 639-653 : ill http://agronomy.emu.ee/vol133/13_3_2_B5.pdf
• Effect of chemical modification of wood flour on the mechanical properties of wood-plastic composites [Electronic resource]Kallakas, Heikko; Shamim, M. A.; Olutubo, T.; Poltimäe, Triinu; Süld, Tiia-Maaja; Krumme, Andres; Kers, Jaan6th International Conference Biosystems Engineering 2015 : 7-8 May 2015, Tartu, Estonia : book of abstracts2015 / p. 94. [CD-ROM] http://bse.emu.ee/BSE2015_Book%20of%20ABSTRACTS_ISBN.pdf
• Influence of birch false heartwood on the physical and mechanical properties of wood-plastic compositesKallakas, Heikko; Ayansola, Gbenga; Tumanov, Tanel; Goljandin, Dmitri; Poltimäe, Triinu; Krumme, Andres; Kers, JaanBioresources2019 / p. 3554-3566 : ill https://doi.org/10.15376/biores.14.2.3554-3566 https://www.scopus.com/sourceid/5900153306 https://www.scopus.com/record/display.uri?eid=2-s2.0-85071130130&origin=inward&txGid=a0ca612eea61409486a491d60b861350 https://jcr.clarivate.com/jcr-jp/journal-profile?journal=BIORESOURCES&year=2022 https://www.webofscience.com/wos/woscc/full-record/WOS:000466449000077
• Mechanical and physical properties of thermally modified wood flour reinforced polypropylene compositesKallakas, Heikko; Martin, Mihkel; Goljandin, Dmitri; Poltimäe, Triinu; Krumme, Andres; Kers, JaanAgronomy research2016 / p. 994-1003 : ill http://ise.elnet.ee/record=b2891902~S1*est https://www.scopus.com/sourceid/21100201050 https://www.scopus.com/record/display.uri?eid=2-s2.0-84969988886&origin=inward&txGid=68ddfb679baa71078c659322e97554a0