Hetkämper, T., Koch, K., Claes, L., &; Henning, B. (2023). Phase-preserving methods to visualise ultrasonic fields with schlieren imaging. Tm - Technisches Messen, 90(2), 103–112.https://doi.org/10.1515/teme-2022-0112 
LibreCat: /record/37543
DOI: 10.1515/teme-2022-0112

Dreiling, D., Itner, D., Hetkämper, T., Birk, C., Gravenkamp, H., &; Henning, B. (2023). Improved determination of viscoelastic material parameters using a pulse-echo measurement setup. SMSI 2023 Conference, 394–395.https://doi.org/10.5162/SMSI2023/P59 
LibreCat: /record/45205
DOI: 10.5162/SMSI2023/P59

Hetkämper, T., Koch, K., Webersen, M., &; Claes, L. (2023). Application-based learning of signal analysis methods with the help of a graphical open-source software. SEFI 51th Annual Conference Proceedings - Engineering Education for Sustainability. SEFI 2023 Annual Conference.https://doi.org/10.21427/159K-G445 
LibreCat: /record/47138
DOI: 10.21427/159K-G445

Hetkämper, T., Claes, L., &; Henning, B. (2023). Vorzeichenrichtige tomographische Rekonstruktion von Ultraschallfeldern mit Hilfe der Schlierentechnik. Tm - Technisches Messen, 90(), 49–54.https://doi.org/10.1515/teme-2023-0069 
LibreCat: /record/48053
DOI: 10.1515/teme-2023-0069

Hetkämper, T. (2022). Visualisierung von Ultraschallfeldern mittels Schlierentechnik und fraktionaler Fouriertransformation.
LibreCat: /record/6561

Hetkämper, T., Claes, L., &; Henning, B. (2022). Schlieren imaging with fractional Fourier transform to visualise ultrasonic fields. Sensoren Und Messsysteme - Beiträge Der 21. ITG/GMA-Fachtagung. 21. ITG/GMA- Fachtagung Sensoren und Messsysteme 2022, Nürnberg.
LibreCat: /record/31331

Claes, L., Chatwell, R. S., Baumhögger, E., Hetkämper, T., Zeipert, H., Vrabec, J., &; Henning, B. (2021). Measurement procedure for acoustic absorption and bulk viscosity of liquids. Measurement, Article 109919.https://doi.org/10.1016/j.measurement.2021.109919 
LibreCat: /record/22925
DOI: 10.1016/j.measurement.2021.109919

Hetkämper, T., Dreiling, D., Claes, L., &; Henning, B. (2021). Tomographie des Schallfelds von Ultraschallwandlern mittels Schlierentechnik. Fortschritte der Akustik - DAGA 2021. DAGA 2021 - 47. Jahrestagung für Akustik.
LibreCat: /record/25880

Hetkämper, T., Krumme, M., Dreiling, D., &; Claes, L. (2020). A modular, scalable open-hardware platform for project-based laboratory courses in electrical engineering studies. SEFI 48th Annual Conference Proceedings - Engaging Engineering Education, 1309–1313.
LibreCat: /record/19502

Claes, L., Steidl, C., Hetkämper, T., &; Henning, B. (2020). Estimation of acoustic wave non-linearity in ultrasonic measurement systems. ArXiv.Org.https://doi.org/10.48550/arXiv.2001.05708 
LibreCat: /record/15489
DOI: 10.48550/arXiv.2001.05708
arXiv: 2001.05708

Hetkämper, T., Claes, L., &; Henning, B. (2019). Evolutionary algorithm for the design of passive electric matching networks for ultrasonic transducers. In 2019 International Congress on Ultrasonics. Bruges.https://doi.org/10.1121/2.0001110 
LibreCat: /record/16076
DOI: 10.1121/2.0001110