SIMBAD references

G. Cortini, Predappio, Italy, reports the discovery of an apparent supernova (mag about 13.7) on several unfiltered CCD images (limiting mag near 18.5) taken on Apr. 13.97 and 14.82 UT during his supernova search program with a 0.35-m telescope at the Monte Maggiore Observatory. The new object is located at R.A. = 12:05:33.6 ± 0s.1, Decl. = +50:32:20 ± 3" (equinox 2000.0), which is 2" west and 5" south of the center of NGC 4088. Nothing is visible at this position on his image taken on Feb. 19.71 (limiting mag about 18.5) or on red and blue Palomar Sky Survey plates. After the object was posted on the Central Bureau's unconfirmed- objects webpage (based on only the first night's observation by Cortini), A. Dimai (Cortina d'Ampezzo, Italy) reported an independent discovery of 2009dd at mag about 13.8 on unfiltered CCD images (limiting mag about 19.0) taken by Elisa Londero (Gemona, Italy) and himself in the course of the CROSS program (cf. IAUC 7373) with the 0.5-m "Ullrich" telescope on Apr. 13.05, providing position end figures 34s.10, 18".6 (offset 1" west and 3" south of the nucleus of the galaxy NGC 4088); confirming images on Apr. 14.80 yield mag about 13.5 for 2009dd. A CROSS image of the same field taken on Feb. 28 showed nothing at the position of 2009dd (limiting mag about 19.0), and it does not appear on Palomar Sky Survey infrared, red, and blue plates. Dimai has posted their discovery image at URL http://www.cortinastelle.it/cross/SN-NGC4088_20090413.jpg.