Optical Spectroscopy and Nebular Oxygen Abundances of the Spitzer/SINGS Galaxies

Optical Spectroscopy of Distant Red Galaxies

Optical Spectroscopy of Halpha Filaments in Cool Core Clusters: Kinematics, Reddening, and Sources of Ionization

Optical spectroscopy of the gamma-ray bright blazars PKS 0447-439 and PMN J0630-24

Optical Spectroscopy of the Somewhat Peculiar Type IIb Supernova 2001ig

Optical Variability and Colour Behaviour of 3C 345

Optical variability of radio-intermediate quasars

Optical vs. infrared studies of dusty galaxies and AGN: (I) Nebular emission lines

Optical-NIR spectra of quasars close to reionization (z~ 6)

Optical/UV/X-ray Insights into the RL--RQ Dichotomy

Optically Faint Radio Sources: Reborn AGN?

Optically faint X-ray sources in the CDFN: Spitzer constraints

Optically Selected BL Lacertae Candidates from the Sloan Digital Sky Survey Data Release Seven

Optically Selected Compact Stellar Regions and Tidal Dwarf Galaxies in (Ultra)-Luminous Infrared Galaxies

Optimal Binning of the Primordial Power Spectrum

Optimal Black Holes are the Cosmological Objects, which Minimize Volume of Information in Areas of the Universe and in the Universe as a Whole

Optimal capture of non-Gaussianity in weak lensing surveys: power spectrum, bispectrum and halo counts

Optimal Constraints on Local Primordial Non-Gaussianity from the Two-Point Statistics of Large-Scale Structure

Optimal filtering of optical and weak lensing data to search for galaxy clusters: application to the COSMOS field

Optimal filters for detecting cosmic bubble collisions