Symbol Glossary

$\phi$	Geodetic latitude
$\theta$	Reduced latitude, defined by Eqn. (2)
$L$	Longitude (difference)
$\alpha$	azimuths, clockwise from N ($\alpha_0$ at equator)
$s$	arc-length along geodesic
$\lambda$	longitude (difference) on auxiliary sphere
$\sigma$	arc-length on auxiliary sphere
$a$	major (equatorial) radius of ellipse
$b$	minor (polar) radius of ellipse
$f$	flattening $b=a(1-f)$
$e$	eccentricity $b^2=a^2(1-e^2)$