Analysis of the 1900Å blend as described in Sect. 3.2 for the 11 xA sources in our work. Abscissa scales are rest frame wavelength in Å. The ordinate scale is the specific flux. Black lines identify the BC of Al IIIλ1860, Si III]λ1892, and CIII]λ1909. The dashed blue line is the multi-component model obtained by specfit. Green lines trace the adopted Fe II (pale) and Fe III templates (dark).