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SS Cyg and HL CMa were observed by IUE for three consecutive nights in November of 1992. During the first two nights, simultaneous photometric ground based observations of SS Cyg were made at the Ball State University Observatory. SS Cyg and HL CMa were observed simultaneously with the 90-inch telescope at the Steward Observatory on the last two nights of this run. These spectroscopic observations covered the wavelength range of 4100 \AA to 5000 \AA, while the spectra taken with the short wavelength camera on IUE resulted in wavelength coverage from 1150 \AA to 1980 \AA. SS Cyg is a U Gem type dwarf nova with an orbital period of 6.6 hours. Good simultaneous UV and optical orbital coverage was obtained for this system. HL CMa is a Z Cam type dwarf nova with an outburst period of 18 days. The AAVSO reports that this system was in outburst 4 days after the observing run. Therefore, HL CMa may have been in a preoutburst state during these observations. The C IV and H \beta emission lines appeared to have weakened during this time.
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