  The melting of the magnetic vortex lattice has been observed in high-Tc
superconductors in many experiments by different groups and is regarded as
confirmed. To date, only one group claims to have observed the vortex-lattice
melting in the low-Tc superconductor Nb3Sn in specific-heat measurements. We
measured the same Nb3Sn single crystal with a differential-thermal analysis
method. We report on the absence of any sign of vortex-lattice melting in our
data and discuss the possible reasons for this discrepancy. In addition we
confirm the observation of a small peak-like anomaly near the transition to
superconductivity which is likely related to thermal fluctuations.
