When to cite your sources
Citing the source of information that is not "common knowledge" is always recommended.
Footnotes or Endnotes?
Helen Schatvet Ullmann, CG, FASG wrote, "Footnotes are much handier if your readers will really use them, but endnotes may seem less intimidating." 1
Footnotes generally work better for longer articles and books than endnotes. This is mostly because all the information on a given page remains in context. Folks are more likely to use notes easily located at the bottom of a page. It is just more convenient to look down the page or scroll a short distance than it is to be flipping/clicking back and forth.
For magazine articles (as opposed to journals or books),2 shorter exchanges and family group sheets, endnotes are often the editors preference or the only really practical solution.
Bibliography
A bibliography is a high level list of sources. On a stand alone basis, a bibliography only works well in short articles in my experience. It's a great addition to footnotes or endnotes for a medium sized work or article. For a larger work, you may find it less useful.
References:
- Helen Schatvet Ullmann, CG, FASG, "Writing a Family Sketch: Register Style" e-article, AmericanAncestors (http://www.americanancestors.org/writing-a-family-sketch/: accessed 2013).
- Michael J. Leclerc and Henry B. Hoff, Genealogical Writing in the 21st Century ..., (Boston, New England HIstoric Genealogical Society, 2006), p. 56.
Other reading:
- Board for Certification of Genealogists, The BCG Genealogical Standards Manual (Orem, Utah: Ancestry Publishing, 2000).
- Joan F. Curran, Madilyn C. Crane, and John H. Wray, authors, edited by Elizabeth Shown Mills, Numbering Your Genealogy: Basic Systems, Complex Families, and International Kin, rev. ed. (Washington: NGS, 2008).
- Michelle Watson, "Footnotes or Endnotes?," GenealogyWise discussion, 8 Oct 2009.