00377nam a22001097a 4500020000800000040001600008082001300024100003200037245007600069260006000145300006200205  qHB.  cFIZZA ISHAQ  a528bAST  aOffice ,  Nautical Almanac.  aThe Astronomical Almanac For the Year 1981 /c Nautical Almanac Office.  aWashington, D.C. :bGovernment Printing Office, c1980.  avarious pagings : illustrations, charts, tables ; c25 cm