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At the Pierre Auger Observatory, cosmic rays (CRs) with energies up to O (100) EeV can be detected and their properties can be measured, including energy, depth of the shower maximum max and arrival direction. The cosmic ray energy can be determined with the 1660 surface detector (SD) stations, which are distributed over an area of 3000 km2 and which detect extensive air showers produced by the primary CR during interactions with the atmosphere. For some events, max can be measured with the fluorescence detector (FD) on dark, cloudless nights. The charge of the primary particle cannot be measured directly, but max is related to it. Both measurements have been combined in [1] to fit a model containing a homogeneous distribution of sources to the data, and to gain knowledge about parameters of the sources of ultra-high-energy CRs. The identification of sources that are powerful enough to accelerate CRs to the highest energies is one of the prime goals of the Pierre Auger Observatory. Here, we demonstrate that by also using the arrival directions as a third observable in the fit, we can additionally model the energy-dependent contribution of a catalog of specific foreground sources.