Optical Spectroscopic Survey of High Latitude WISE Selected Sources

Optical Variability of the Radio Source J 1128+5925 -- II. Confirmation of its Optical Quietness

Optical/infrared observations of the X-ray burster KS1731-260 in quiescence

Optical/IR counterpart to the resolved X-ray jet source CXO J172337.5-373442 and its distance

Orbital Eccentricity as a probe of Thick Disk Formation Scenarios

Orbital Eccentricity Distribution of Solar-Neighbour Halo Stars

Orbital Support of Fast and Slow Inner Bars in Double Barred Galaxies

Orbits of LMC/SMC with recent ground-based proper motions

Orbits of nearby planetary nebulae and their interaction with the interstellar medium

Order and Chaos in a Three-dimensional Binary System of Interacting Galaxies

Order and chaos in a triaxial galaxy model with a dark halo component

Ordered and chaotic spirals in disk galaxies

Organic chemistry of low-mass star-forming cores I: 7 mm spectroscopy of Chamaeleon MMS1

Origin and Dynamical Support of Ionized Gas in Galaxy Bulges

Origin and Evolution of the Abundance Gradient along the Milky Way Disk

Origin and structure of the Galactic disc(s)

Origin of chemical and dynamical properties of the Galactic thick disk

Origin of cosmic rays and evolution of spallogenic nuclides Li, Be and B

Origin of Molecular Outflow Determined from Thermal Dust Polarization

Origin of multiple nuclei in ultraluminous infrared galaxies