Book excerpt: Tables of asymptotic directions and vertical cutoff rigidities for a five degree by fifteen degree world grid are presented. These values were obtained by the integration of vertically incident cosmic-ray trajectories through the International Geomagnetic Reference Field with time derivatives applied so that the coefficients form a quiescent model of the geomagnetic field for Epoch 1975.0. The table of asymptotic directions contains the asymptotic latitudes and longitudes which specify the direction of approach, from interplanetary space, of a cosmic-ray particle. These asymptotic directions are given for each grid point for specific rigidities above the main cone cutoff rigidity. The table of vertical cutoff rigidities contains the geographic coordinates and L value of each location together with the main cone cutoff rigidity, the Stoermer cutoff rigidity, and the effective cutoff rigidity.