Analysis of information sources in references of the Wikipedia article "Gregorian calendar" in English language version.
Annus Cycli decennouennalis, qui dr Aureus numerus est 6. terminaturque simulcu ipso anno Domini 1582 in mése Decembri. In mense autem Ianuario initium sumit alius annus Domini , nempe 1583. & in eodem mense Ianuario aslumitur etiam alius annuis Aurei numeri, nimirum 7.[The year of the ten-year cycle, which is the golden number 6, ends at the same time in the year of the Lord 1582 in the month of December. And in the month of January begins another year of the Lord, that is, 1583. And in the same month of January also another year of the golden number is ushered in, namely 7.]
He remarks that both the Alphonsine and the Prutenic Tables are several hours wrong with regard to the time of the equinoxes and solstices.
He noted on one occasion that the Alphonsine tables differed from the Prutenic by nineteen hours as to the time of the vernal equinox of 1588.
{{cite book}}: CS1 maint: location missing publisher (link)Before 1752, parish registers, in addition to a new year heading after 24th March showing, for example '1733', had another heading at the end of the following December indicating '1733/4'. This showed where the Historical Year 1734 started even though the Civil Year 1733 continued until 24th March. ... We as historians have no excuse for creating ambiguity and must keep to the notation described above in one of its forms. It is no good writing simply 20th January 1745, for a reader is left wondering whether we have used the Civil or the Historical Year. The date should either be written 20th January 1745 OS (if indeed it was Old Style) or as 20th January 1745/6. The hyphen (1745-6) is best avoided as it can be interpreted as indicating a period of time.
Before 1752, parish registers, in addition to a new year heading after 24th March showing, for example '1733', had another heading at the end of the following December indicating '1733/4'. This showed where the Historical Year 1734 started even though the Civil Year 1733 continued until 24th March. ... We as historians have no excuse for creating ambiguity and must keep to the notation described above in one of its forms. It is no good writing simply 20th January 1745, for a reader is left wondering whether we have used the Civil or the Historical Year. The date should either be written 20th January 1745 OS (if indeed it was Old Style) or as 20th January 1745/6. The hyphen (1745-6) is best avoided as it can be interpreted as indicating a period of time.