English: The true title of Led Zeppelin IV

The original four symbols were created by Led Zeppelin in 1971, probably from the following sources:

• 1. Jimmy Page's Zoso symbol from a sigil for Saturn from page 51 of an 1850 reprint of a 1521 French book Dragon Rouge and Poulet Noire (The Red Dragon and The Black Hen); also seen on page 31 of Frinellan's 1844 book Le Triple Vocabulaire Infernal Manuel du Demonomane. A variation of the symbol also appears in Jerome Cardan's 1557 book De rerum varietate (page 789 of this 1580 reprint).
• 2. John Paul Jones' symbol (non-interlaced triquetra overlaying a circle) is from page 33 of Rudolf Koch's 1930 book The Book of Signs (Koch died in 1934) where it is annotated as a sign "to exorcise evil spirits".
• 3. John Bonham's symbol (three intersecting circles) is from page 32 of the same book by Rudolf Koch, given as an "early sign for the Trinity".
• 4. Plant's feather symbol is likely a simple merging of two symbols from the "Feather Symbol of Truth" illustration on page 105 of James Churchward's 1933 book The Sacred Symbols of Mu (Churchward died in 1936)

Source of research: Duncan from http://www.inthelight.co.nz/ledzep/zososymbol.htm