(1)
Chung-In Adamenko, Soo-Young Pandey, Sahng-Kyoon George, and T. F. Yoo, Viscosity and ultrasonic attenuation in 4 He below 0.6 K, Low Temp. Phys. 23, (1997) [Fiz. Nizk. Temp. 23, 537-545, (1997)].