Superconductivity in the ternary intermetallics Yb${\mathrm{Pd}}_2$${\mathrm{Ge}}_2$, La${\mathrm{Pd}}_2$${\mathrm{Ge}}_2$, and La${\mathrm{Pt}}_2$${\mathrm{Ge}}_2$

Superconductivity is found to exist in the ternary intermetallics Yd${\mathrm{Pd}}_2$ ${\mathrm{Ge}}_2$, La${\mathrm{Pd}}_2$ ${\mathrm{Ge}}_2$, and La${\mathrm{Pt}}_2$ ${\mathrm{Ge}}_2$. Superconductivity-onset temperatures are 1.17, 1.12, and 0.55 K, respectively. Superconductivity was found neither in Yb${\mathrm{Cu}}_2$ ${\mathrm{Ge}}_2$ nor in bulk Ce${\mathrm{Cu}}_2$ ${\mathrm{Si}}_2$, the latter in contrast to previously published work.