Temperature distribution of the cold dust for the WISSH quasars (blue) compared to: high-z IR luminous quasars from Beelen et al. (2006), Leipski et al. (2014), Valiante et al. (2011) (upper panel); local PG quasars from Petric et al. (2015) and SDSS quasars at z< 4.7 from Ma & Yan (2015) (central panel); and galaxies from Magdis et al. (2012), Santini et al. (2014), Melbourne et al. (2012), Chapman et al. (2005), Magnelli et al. (2014), Miettinen et al. (2015) (lower panel). Note that all these works have assumed different values of both the coefficient of the modified blackbody β and the dust absorption coefficient k₀.