Confusion over boiling point of gallium
This question has been recently raised in Chemistry &amp; Engineering Letters. The CRC Handbook (2017) in section "MELTING, BOILING, TRIPLE, AND CRITICAL POINTS OF THE ELEMENTS" [1, p. 4-117] lists the following values for gallium, quoting original publication [2]:

\begin{align}
t_\mathrm{tp} (\ce{Ga}) &amp;= \pu{29.7666 ^\circ C} \\
t_\mathrm{m} (\ce{Ga}) &amp;= \pu{29.7646 ^\circ C} \\
t_\mathrm{b} (\ce{Ga}) &amp;= \pu{2229 ^\circ C} \\
\end{align}


  [...] values are given for the solid-liquid-gas triple-point temperature $t_\mathrm{tp}$ and pressure $p_\mathrm{tp}$; normal melting point at $\pu{101.325 kPa}$ pressure $t_\mathrm{m}$; normal boiling point $t_\mathrm{b}$; and critical temperature $t_\mathrm{c}$ and pressure $p_\mathrm{c}$. All temperatures are on the ITS-90 scale.


References


Haynes, W. M.; Lide, D. R.; Bruno, T. J. CRC Handbook of Chemistry and Physics: A Ready-Reference Book of Chemical and Physical Data.; 2017; Vol. 97. ISBN 978-1-4987-5429-3.  
Geiger, F.; Busse, C. A.; Loehrke, R. I. Int J Thermophys 1987, 8 (4), 425–436 DOI: 10.1007/BF00567103.