  Ultra-High-Energy (UHE) ($E>100 $TeV) Extensive Air Showers (EASs) have been
monitored for a period of five years (1997-2003), using a small array of
scintillation detectors in Tehran, Iran. The data have been analyzed to take in
to account of the dependence of source counts on zenith angle. Because of
varying thickness of the overlaying atmosphere, the shower count rate is
extremely dependent on zenith angle. During a calendar year different sources
come in the field of view of the array at varying zenith angles and have
different effective observation time equivalent to zenith in a day. High energy
gamma-ray sources from the EGRET third catalogue where observed and the data
were analyzed using an excess method. Upper limits were obtained for 10 EGRET
sources. Then we investigated the EAS event rates for these 10 sources and
obtained a flux for each of them using parameters of our experiment results and
simulations. Finally we investigated the gamma-ray spectrum in the UHE range
using these fluxes with reported fluxes of the EGRET sources.
