%0 Journal Article %A P. Chithralekha %A C. Murugeswari %A K. Ramachandran %A R. Srinivasan %T The study on ultrasonic velocities of Co$_x$Fe$_{3-x}$O$_4$ nanoferrofluid prepared by co-precipitation method %J Nanosistemy: fizika, himiâ, matematika %D 2016 %P 558-560 %V 7 %N 3 %I mathdoc %U http://geodesic.mathdoc.fr/item/NANO_2016_7_3_a28/ %G en %F NANO_2016_7_3_a28