The [[Supreme Court of the United States|U.S. Supreme Court]] uses its own unique citation style in its opinions, even though most of the justices and their [[law clerk]]s obtained their [[Legal education in the United States|legal education]] at law schools that use ''The Bluebook''.<ref name="Salmon1">{{cite journal|last1=Salmon|first1=Susie|title=Shedding the Uniform: Beyond 'A Uniform System of Citation' to a More Efficient Fit|journal=Marquette Law Review|date=2016|volume=99|page=792|url=http://scholarship.law.marquette.edu/cgi/viewcontent.cgi?article=5289&context=mulr|accessdate=28 April 2017|publisher=Marquette University|location=Milwaukee}}</ref> Furthermore, many [[state court (United States)|state courts]] have their own citation rules that take precedence over ''The Bluebook'' for documents filed with those courts. Some of the local rules are simple modifications to ''The Bluebook'' system, such as [[Maryland]]'s requirement that citations to Maryland cases include a reference to the official Maryland reporter. [[Delaware]]'s [[Supreme Court of Delaware|Supreme Court]] has promulgated rules of citation for unreported cases markedly different from ''The Bluebook'' standards, and custom in that state as to the citation format of the [[Delaware Code]] also differs from ''The Bluebook''.<ref>[http://courts.delaware.gov/forms/download.aspx?id=39368 Rule 14(g)] {{webarchive|url=https://web.archive.org/web/20160303190900/http://courts.delaware.gov/forms/download.aspx?id=39368 |date=2016-03-03 }}, Rules of the Supreme Court of the State of Delaware.</ref> In other states, notably [[New York (state)|New York]], [[Texas]], and [[Michigan]], the local rules are different from ''The Bluebook'' in that they use their own style guides. Attorneys in those states who practice both in federal court and state court must be able to switch seamlessly between citation styles depending upon whether their work product is intended for a federal or state court. Since 2008, [[California]] rules of court have allowed citations in Bluebook form as well as the state's own style manual,<ref>Cal. Rule of Court 1.200</ref> but many practitioners and courts continue to recommend following the ''California Style Manual'' in California courts.<ref name="Salmon2">{{cite journal|last1=Salmon|first1=Susie|title=Shedding the Uniform: Beyond 'A Uniform System of Citation' to a More Efficient Fit|journal=Marquette Law Review|date=2016|volume=99|page=791|url=http://scholarship.law.marquette.edu/cgi/viewcontent.cgi?article=5289&context=mulr|accessdate=28 April 2017|publisher=Marquette University|location=Milwaukee}}</ref>

The cover of the 1926 ''A Uniform System of Citation'' was green. The color was "brown from the second (1928) edition through the fifth (1936) edition. It was only with the sixth (1939) edition that it became blue."<ref name="auto">Shapiro and Krishnaswami.</ref> In 1939, the cover of the book was changed from brown to a "more patriotic blue" allegedly to avoid comparison with a color associated with [[Nazi Germany]].<ref>A. Darby Dickerson, ''An Un-Uniform System of Citation: Surviving with the New Bluebook'', 26 {{smallcaps|Stetson L. Rev.}} 53, 58-60 (1996). According to Shapiro and Krishnaswami, however, "The abandonment of brown is often attributed to the association of that color with Nazi Germany in the 1930s, but that idea appears to trace to a joke by Alan Strasser," in [http://heinonline.org/HOL/Page?men_tab=srchresults&handle=hein.journals/hcrcl12&id=515&size=2&collection=journals&terms=Alan%20Strasser&termtype=phrase&set_as_cursor=10 ''Technical Due Process: ?''], 12 {{smallcaps|Harv. C.R.-C.L. Rev.}} 507, 508 (1977). Strasser states, referring to the eleventh edition's change of cover color to white with a blue border promising a "new life," that "the 1939 ''Blue Book'' had electrified the nation by parading patriotic blue covers instead of the Germanic brown ones that had disgraced the 1936 edition." ''Id''. (footnote omitted).</ref> The eleventh edition, published in 1967, was actually white with a blue border.<ref>[http://blawg.law.sc.edu/2015/07/13/all-the-fun-facts-about-the-bluebook/ ''All the Fun Facts about the Bluebook'']{{dead link|date=December 2017 |bot=InternetArchiveBot |fix-attempted=yes }}.</ref> The cover color returned to blue in the twelfth edition of 1976.<ref>Strasser, at 508. Strasser states that the first printing was a "timid" blue-gray but later printings were a "more self-assured" navy blue. ''Id''. n.9.</ref>

California used to require use of the ''California Style Manual''.<ref>{{smallcaps|Edward W. Jessen}}, {{smallcaps|California Style Manual}} 1 (4th ed. 2000).</ref> In 2008, the [[California Supreme Court]] issued a rule giving an option of using either the ''California Style Manual'' or ''The Bluebook''.<ref>2013 Calif. R. of Ct. 1.200; {{smallcaps|The Bluebook: A Uniform System of Citation}} 30 (Mary Miles Prince ed., 19th ed. 2010).</ref> The two styles are significantly different in citing cases, in use of ''Ibid'' or ''Id.'' (for ''{{lang|la|Idem}}''), and in citing books and journals.<ref>''[http://libguides.law.ucla.edu/loader.php?type=d&id=92912 Legal Research and Writing Manual]{{dead link|date=December 2017 |bot=InternetArchiveBot |fix-attempted=yes }}'', {{smallcaps|UCLA School of Law}} (2013).</ref> Michigan uses a separate official citation system, issued as an administrative order of the Michigan Supreme Court.<ref>Elan S. Nichols, ''Checklists for Drafting, Formatting, and Submitting Litigation and Other Documents: Instructive Material for Law Students Practicing in Law School Clinics, and Reminders for the Practicing Attorney and Her Staff'', 15 {{smallcaps|T.M. Cooley J. Prac. & Clinical L.}} 57, 58 (2013).</ref> The primary difference is that the Michigan system "omits all periods in citations, uses italics somewhat differently, and does not use 'small caps.'"<ref>Nichols, at 58 n.3.</ref> As noted, Texas merely supplements ''The Bluebook'' with items that are unique to Texas courts, such as citing to cases when Texas was an independent republic,<ref>{{smallcaps|The Greenbook}}, at 101.</ref> petition and writ history,<ref>{{smallcaps|The Greenbook}}, at 20-26.</ref> [[Texas Attorney General|Attorney General]] Opinions,<ref>{{smallcaps|The Greenbook}}, at 76-78.</ref> and similar issues.