↑ Mandryk, DeeAnn (ngày 25 tháng 10 năm 2005). Canadian Christmas Traditions. James Lorimer & Company. tr. 67. ISBN9781554390984. The eight-pointed star became a popular manufactured Christmas ornament around the 1840s and many people place a star on the top of their Christmas tree to represent the Star of Bethlehem.
↑ Jones, David Albert (ngày 27 tháng 10 năm 2011). Angels. Oxford University Press. tr. 24. ISBN9780191614910. The same ambiguity is seen in that most familiar of angels, the angel on top of the Christmas tree. This decoration, popularized in the nineteenth century, recalls the place of the angels in the Christmas story (Luke 2.9–18).
↑ Peter Mazar (2000). School Year, Church Year: Customs and Decorations for the Classroom. Liturgy Training Publications. tr. 161. ISBN1568542402.
↑ Maas, R. P.; Patch, S. C.; Pandolfo, T. J. (2004). “Artificial Christmas trees: How real are the lead exposure risks?”. Journal of Environmental Health. 67 (5): 20–24, 32. PMID15628192.