Isophotal analyses developed in recent years (CCD images and numerical mapping techniques) have revealed that triaxial structures are frequently present in bulges of spirals and in elliptical galaxies. In the first case, these non-axisymmetric oval structures have been proposed as the corresponding sources of the energy necessary to maintain the

We describe a method of determining the system parameters in non-eclipsing interacting binaries. We find that the extent to which an observer sees the shape of the Roche lobe of the secondary star governs the amount of distortion of the absorption-line profiles. The width and degree of asymmetry of the phase-resolved absorption-line profiles show a

We have performed photometric optical observations of a sample of 17 core-dominated radio-loud quasars (CRLQs) and 17 radio-quiet quasars (RQQs). The aims were to confirm the existence of microvariations in strictly radio-quiet objects and to compare the properties of the variations in both types of quasars. Great care was taken to avoid selection

IAUC 6933 available at Central Bureau for Astronomical Telegrams.

IAUC 6931 available at Central Bureau for Astronomical Telegrams.

The three-dimensional P-wave velocity structure of Mt. Etna is determined to depths of 15 km by tomographic inversion of first arrival times from local earthquakes recorded by a network of 29 permanent and temporary seismographs. Results show a near-vertical low-velocity zone that extends from beneath the central craters to a depth of 10 km. This