Which scientist experimentally proved that $\text{DNA}$ is the sole genetic material in bacteriophage?

Alfred Hershey and Martha Chase ($1952$) used radioactive isotopes of phosphorus (${}^{32}\text{P}$) and sulfur (${}^{35}\text{S}$) to label DNA and protein of $T_2$ bacteriophage, respectively. They proved that only the DNA enters the bacteria, establishing it as the genetic material.