1. The control of reinforced concrete prefabricated product using ultrasonic surface waves;Dzenis;Concrete and Ferroconcrete,1974
2. The methods of exciting and receiving ultrasonic surface waves in frequency range 40–120kHz;Noviks,1980
3. Mechanical Waveguides;Redwood,1960
4. Der Ultraschall und Seine Anwendung in Wissenschaft und Technik;Bergmann,1954
5. Application of the ultrasonic transducers with point contact for the nondestructive testing, “Zinatne”;Dzenis,1987