Basics of Ring Theory -- Basics of Polynomial Theory -- Groebner Basis -- Polynomial Resultants -- Gauss-Jacobi Combinatorial Algorithm -- Local versus Global Positioning Systems -- Partial Procrustes and the Orientation Problem -- Positioning by Ranging -- From Geocentric Cartesian to Ellipsoidal Coordinates -- Positioning by Resection Methods -- Positioning by Intersection Methods -- GPS Meteā¦