The symbol 
is occasionally used in German literature
to refer to the binary logarithm. However, the
United States Department of Commerce recommends that the notation 
be used for this purpose (Taylor 1995, p. 33).
Ld
See also
Common Logarithm, Lg, Ln, Logarithm, Napierian Logarithm, Natural LogarithmExplore with Wolfram|Alpha
References
Taylor, B. N. Guide for the Use of the International System of Units (SI). United States Department of Commerce. NIST Special Publication 811, p. 33, 1995. http://physics.nist.gov/cuu/pdf/sp811.pdf.Referenced on Wolfram|Alpha
LdCite this as:
Weisstein, Eric W. "Ld." From MathWorld--A Wolfram Web Resource. https://mathworld.wolfram.com/Ld.html