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We have obtained quasi-simultaneous ultraviolet-optical spectra for 22 out of23 quasars in the complete PG-X-ray sample with redshift, z<0.4, and M_B<-23.The spectra cover rest-frame wavelengths from at least Lyman-alpha to H-alpha.Here we provide a detailed description of the data, including carefulspectrophotometry and redshift determination. We also present directmeasurements of the continua, strong emission lines and features, includingLyman-alpha, SiIV+OIV], CIV, CIII], SiIII], MgII, H-beta, [OIII],He5876+NaI5890,5896, H-alpha, and blended iron emission in the UV and optical.The widths, asymmetries and velocity shifts of profiles of strong emissionlines show that CIV and Lyman-alpha are very different from H-beta and H-alpha.This suggests that the motion of the broad line region is related to theionization structure, but the data appears not agree with the radiallystratified ionization structure supported by reverberation mapping studies, andtherefore suggest that outflows contribute additional velocity components tothe broad emission line profiles.

Spectral Properties from Lyα to Hα for an Essentially Complete Sample of Quasars. I. Data