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\cj{\sb U N I V E R S A L \ \  C A L E N D A R}
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\cj{\si Author Valentin Hristov (Bulgaria)}
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\+ & & & & &\hr &\hrr &\hr &\hr &\hr &\hr &\hr & & & & & & & &\cr
\+ & & & & &\vr\cd{Year in the century} & & & & & & &\vr & & & & & & & &\cr
\+ & & & & &\hr &\hr &\hr &\hr &\hr &\hr &\hr & & & & & & & &\cr
\+ &\cf{\sb Instructions} & & & &\vr\cc{\si 00} &\cc{01} &\cc{02}&\cc{03} & &\cc{\sb 04} &\cc{05} &\vr\ce{The date Thursday} & & & & & & & &\cr
\+ &\cf{for use} & & & &\vr\cc{06} &\cc{07} & &\cc{\sb 08} &\cc{09} &\cc{10} &\cc{11} &\vr\ce{October 4, 1582 (old style)} & & & & & & & &\cr
\+ &\cf{\sb 1.} & & & &\vr &\cc{\sb 12} &\cc{13} &\cc{14} &\cc{15}& &\cc{\sb 16} &\vr\ce{is followed by the date Friday} & & & & & & & &\cr
\+ &\cf{Year in century} & & & &\vr\cc{17} &\cc{18} &\cc{19} & &\cc{\sb 20} &\cc{21} &\cc{22} &\vr\ce{October 15, 1582 (new style).} & & & & & & & &\cr
\+ &\cf{(intersect!)\ $\downarrow$} & & & &\vr\cc{23} & &\cc{\sb 24} &\cc{25} &\cc{26} &\cc{27} & &\vr & & & & & & & &\cr
\+ &\cf{Month \ $\to$ \ {\sb K}} & & & &\vr\cc{\sb 28} &\cc{29}&\cc{30} &\cc{31} & &\cc{\sb 32} &\cc{33} &\vr\ce{In Bulgaria the date Thursday} & & & & & & & &\cr
\+ &\cf{{\sb K} - key day} & & & &\vr\cc{34} &\cc{35} & &\cc{\sb 36} &\cc{37} &\cc{38} &\cc{39} &\vr\ce{March 31, 1916 (old style)} & & & & & & & &\cr
\+ &\cf{(remember {\sb K}!)} & & & &\vr &\cc{\sb 40} &\cc{41} &\cc{42} &\cc{43} & &\cc{\sb 44} &\vr\ce{is followed by the date Friday} & & & & & & & &\cr
\+ &\vr &\vr\cg{\sb 2.} & & &\vr\cc{45} &\cc{46} &\cc{47} & &\cc{\sb 48} &\cc{49} &\cc{50} &\vr\ce{April 14, 1916 (new style).} & & & & & & & &\cr
\+ &\vr\cc{\ \sb K} &\vr\cg{$\leftarrow$ Century} & & &\vr\cc{51} & &\cc{\sb 52} &\cc{53} &\cc{54} &\cc{55} & &\vr & & & & & & & &\cr
\+ &\vr &\vr\cg{(remember} & & &\vr\cc{\sb 56} &\cc{57} &\cc{58} &\cc{59} & &\cc{\sb 60} &\cc{61} &\vr\ce{The {\sb leap} {\si years} and} & & & & & & & &\cr
\+ &\vr &\vr\cg{col. with {\sb K}!)} & & &\vr\cc{62} &\cc{63} & &\cc{\sb 64} &\cc{65} &\cc{66} &\cc{67} &\vr\ce{\si exact centuries} & & & & & & & &\cr
\+ &\vr &\vr\cg{\sb 3.} & & &\vr &\cc{\sb 68} &\cc{69} &\cc{70} &\cc{71} & &\cc{\sb 72} &\vr\ce{are in {\sb bold}.} & & & & & & & &\cr
\+ &\vr\cc{\ \sb D} &\vr\cg{$\leftarrow$ Date} & & &\vr\cc{73} &\cc{74} &\cc{75} & &\cc{\sb 76} &\cc{77} &\cc{78} &\vr\ce{{\si January} and {\si February}} & & & & & & & &\cr
\+ &\vr &\vr\cg{{\sb D} - day} & & &\vr\cc{79} & &\cc{\sb 80} &\cc{81} &\cc{82} &\cc{83} & &\vr\ce{in {\sb leap} years are also} & & & & & & & &\cr
\+ &\cf{(in remembered} & & & &\vr\cc{\sb 84} &\cc{85} &\cc{86}&\cc{87} & &\cc{\sb 88} &\cc{89} &\vr\ce{in {\sb bold} -- {\sb Jan} and {\sb Feb}.} & & & & & & & &\cr
\+ & & & & & & & & & & & &\hr &\hr &\hr &\hr &\hr &\hr &\hr &\hr &\cr
\+ &\cf{column)} & & & &\vr\cc{90} &\cc{91} & &\cc{\sb 92} &\cc{93} &\cc{94} &\cc{95} &\vr\ci{Full centuries} & & & & & & & &\vr\cr
\+ &\hr &\hr &\hr &\hr & & & & & & & &\hr &\hr &\hr &\hr &\hr &\hr &\hr &\hr &\cr
\+ &\vr\cf{Month} & & & &\vr &\cc{\sb 96} &\cc{97} &\cc{98} &\cc{99} & & &\vr\ch{Old style} & & & & &\vr\cg{New style} & & &\vr\cr
\+ &\hr &\hr &\hr &\hr &\hr &\hr &\hr &\hr &\hr &\hr &\hr &\hr &\hr &\hr &\hr &\hr &\hr &\hr &\hr &\cr
\+ &\vr & &\cc{Jun} & &\vr\cc{Mo} &\cc{Tu} &\cc{We} &\cc{Th} &\cc{Fr} &\cc{\sb Sa} &\cc{\sb Su} &\vr\cc{\sb \ 1} &\cc{\sb \ 8} &\cc{\sb 15} &\cc{\sb 22} &\cc{\sb 29} &\vr & & &\vr\cr
\+ &\vr\cc{Dec} &\cc{Sep} & & &\vr\cc{Tu} &\cc{We} &\cc{Th} &\cc{Fr} &\cc{\sb Sa} &\cc{\sb Su} &\cc{Mo} &\vr\cc{\sb \ 2} &\cc{\sb \ 9} &\cc{\sb 16} &\cc{\sb 23} &\cc{\sb 30} &\vr &\cc{18} &\cc{22} &\vr\cr
\+ &\vr &\cc{Jul} &\cc{Apr} &\cc{\sb Jan} &\vr\cc{We} &\cc{Th} &\cc{Fr} &\cc{\sb Sa} &\cc{\sb Su} &\cc{Mo} &\cc{Tu} &\vr\cc{\sb \ 3} &\cc{\sb 10} &\cc{\sb 17} &\cc{\sb 24} &\cc{\sb 31} &\vr & & &\vr\cr
\+ &\vr\cc{Oct} & & &\cc{Jan} &\vr\cc{Th} &\cc{Fr} &\cc{\sb Sa} &\cc{\sb Su} &\cc{Mo} &\cc{Tu} &\cc{We} &\vr\cc{\sb \ 4} &\cc{\sb 11} &\cc{\sb 18} &\cc{\sb 25} & &\vr\cc{15} &\cc{19} &\cc{23} &\vr\cr
\+ &\vr & &\cc{May} & &\vr\cc{Fr} &\cc{\sb Sa} &\cc{\sb Su} &\cc{Mo} &\cc{Tu} &\cc{We} &\cc{Th} &\vr\cc{\sb \ 5} &\cc{\sb 12} &\cc{\sb 19} &\cc{\sb 26} & &\vr\cc{\sb 16} &\cc{\sb 20} &\cc{\sb 24} &\vr\cr
\+ &\vr &\cc{Aug} & &\cc{\sb Feb} &\vr\cc{\sb Sa} &\cc{\sb Su} &\cc{Mo} &\cc{Tu} &\cc{We} &\cc{Th} &\cc{Fr} &\vr\cc{\sb \ 6} &\cc{\sb 13} &\cc{\sb 20} &\cc{\sb 27} & &\vr & & &\vr\cr
\+ &\vr\cc{Nov} & &\cc{Mar} &\cc{Feb} &\vr\cc{\sb Su} &\cc{Mo} &\cc{Tu} &\cc{We} &\cc{Th} &\cc{Fr} &\cc{\sb Sa} &\vr\cc{\sb \ 7} &\cc{\sb 14} &\cc{\sb 21} &\cc{\sb 28} & &\vr\cc{17} &\cc{21} &\cc{25} &\vr\cr
\+ &\hr &\hr &\hr &\hr &\hr &\hr &\hr &\hr &\hr &\hr &\hr &\hr &\hr &\hr &\hr &\hr &\hr &\hr &\hr &\cr
\+ & & & & &\vr\cd{Day} & & & & & & &\vr\ch{Date} & & & & &\vr & & &\cr
\+ & & & & &\hr &\hr &\hr &\hr &\hr &\hr &\hr &\hr &\hr &\hr &\hr &\hr & & & &\cr
}
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\centerline{\sb Detailed description of the steps}
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All steps use the central rectangle with the names of the days of the week.
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{\sb 1.}
Intersect the horizontal row containing the month (left) and the
vertical
column containing the last two digits of the year (above) to find the
{\sb key day K}. Remember it just as a symbol to be used in Step 2! (Be careful if the
month is January or February. For leap years (see Note: below)
use {\sb Jan} and {\sb Feb}.)
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{\sb 2.}
Find the full centuries (right) in one of the  rectangles in
accordance with the style -- old or new. In the horizontal row with
the centuries find the key day {\sb K} from Step 1. Remember {\sb
the column} containing {\sb K} in the central rectangle for Step 3!
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{\sb 3.}
The rectangle, used in Step 2 for old style centuries,
is now used for the dates of the month. Together with the column
remembered in Step 2 it gives the month calendar, i.e. intersect the
horizontal row with the date of the month and the remembered
column to find the {\sb day of the week}.

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{\sb Note:} Leap years in the old as well as in the new style
are those which can be divided by 4 without remainder.
There are {\sb exceptions} only for the {\si new} style:
the exact centuries (ending with {\si 00}\/), which cannot be
divided by 400 without remainder, are {\si not} leap years.
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