Özgüç, A., Sağlamsaatçi, M., “Solar Rotation Rate from Stable Sunspot Tracings”, Astrophysics and Space Science, 153, 2, 345-349, 1989. Dil Türkçe
Aslan, Z., Aydın, C., Tunca, Z., Demircan, O., Derman, E., Gölbaşı, O., Marsoğlu, A., “Site Testing for an Optical Observatory in Turkey”, Astronomy and Astrophysics, 208, 1-2, 385-391, 1989. Dil Türkçe
Ataç, T., “Relation of the Fluctuations of Some of the Solar Activity Indexes”, Astrophysics and Space Science, 153, 1, 173-176, 1989. Dil Türkçe
Özgüç, A., Ataç, T., “Periodic Behavior of Solar Flare Index During Solar Cycle-20 and Cycle-21”, Solar Physics, 123, 2, 357-365, 1989. Dil Türkçe
Ataç, T., “On the Short Term Variations of Solar Activity During Solar Cycle-21”, Earth Moon and Planets, 47, 2, 165-170, 1989. Dil Türkçe
Özgüç, A., “On the Longitudinal Distribution of the Solar Surges”, Solar Physics, 123, 2, 381-383, 1989. Dil Türkçe
Altaş, L., “Major Flare Effects on the Intensity of the Green Corona and Geomagnetic Activity”, Earth Moon and Planets, 46, 2, 127-134, 1989. Dil Türkçe
Sarıbudak, M., Sanver, M., Ponat, E., “Location of the Western Pontides, NW Turkey, During Triassic Time Preliminary Paleomagnetic Results”, Geophysical Journal-Oxford, 96, 1, 43-50, 1989. Dil Türkçe
Özgüç, A., Düzgelen, A., “Distribution of lde Flares on the Sun During Solar Cycle-20 and Cycle-21”, Astrophysics and Space Science, 162, 1, 27-33, 1989. Dil Türkçe
Kocasoy, G., “A Method for Prediction of Extent of Microbial Pollution of Seawater and Carrying Capacity of Beaches”, Environmental Management, 13, 4, 469-475, 1989. Dil Türkçe
