SIMBAD references

B. E. Schaefer, Louisiana State University, writes that a previously unknown eruption of the recurrent nova U Sco was discovered on Harvard College Observatory archival photographs: plate AC18624 shows U Sco at B = 9.1 (near maximum brightness) on 1917 Mar. 6. With eruptions of U Sco having occurred in 1906, 1917, 1936, 1945, 1969, 1979, 1987, and 1999, Schaefer notes that U Sco has a fairly constant recurrence cycle of 8-12 yr – with about 25 percent of the outbursts being missed due to proximity to the sun (including potential missed outbursts around 1926 and 1957) – adding that the next U Sco eruption should occur sometime during 2007-2011.