ALEXANDRU POP, ADRIAN CRISTEA, VLAD TURCU

*Astronomical Institute of the Romanian Academy*

*Astronomical Observatory Cluj-Napoca*

*Str. Ciresilor 19, RO-3400 Cluj-Napoca, Romania*

*E-mail: apop@academie.cj.edu.ro, acristea@usa.net*

**I. SUNSPOT
AND RADIO
ACTIVITY**

GEORGETA Maris, ADRIAN Oncica, MIRUNA DANIELA Popescu

*Astronomical Institute of the Romanian Academy*

*Str. Cutitul de Argint 5, RO-75212 Bucharest, Romania*

*E-mail: gmaris@aira.astro.ro, adrian@aira.astro.ro,
miruna@aira.astro.ro*

**IN PLANAR
POTENTIALS**

GEORGE BOZIS ^{1},
MIRA-CRISTIANA ANISIU ^{2}

^{1} *Department of Physics,
University of Thessaloniki*

*GR-54006 Thessaloniki, Greece*

*E-mail: gbozis@ccf.auth.gr*

^{2} *"Tiberiu Popoviciu"
Institute of Numerical Analysis*

*P. O. Box 68, RO-3400 Cluj-Napoca, Romania*

*E-mail: mira@math.ubbcluj.ro*

**IN THE
PHOTOGRAVITATIONAL MODEL**

**OF CONSTANTIN
POPOVICI**

VASILE MIOC

*Astronomical Institute of the Romanian Academy*

*Str. Cutitul de Argint 5, RO-75212 Bucharest, Romania*

*E-mail: vmioc@aira.astro.ro*

CRISTINA BLAGA

*Astronomical Institute of the Romanian Academy*

*Astronomical Observatory Cluj-Napoca*

*Str. Ciresilor 19, RO-3400 Cluj-Napoca, Romania*

*E-mail: cpblaga@math.ubbcluj.ro*

CRISTINA STOICA ^{1},
VASILE MIOC ^{2}

^{1} *University of Victoria,
Department of Mathematics and Statistics*

*Victoria, B. C., V8W 3P4, Canada*

*E-mail: cstoica@math.uvic.ca*

^{2} *Astronomical Institute
of the Romanian Academy*

*Str. Cutitul de Argint 5, RO-75212 Bucharest, Romania*

*E-mail: vmioc@aira.astro.ro*

**FOR HAMILTONIAN
SYSTEMS**

C?T?LIN CUCU-DUMITRESCU

*Computer M&S 95*

*Bd. Aviatorilor 23, Bucharest, Romania*

*E-mail: ufh@pcnet.ro*

**OF THE
GEOPOTENTIAL ON
GPS SATELLITE
ORBITS**

STELIAN COJOCARU

*Romanian Naval Academy, Navigation Department*

*Str. Fulgerului 1-3, RO-8700 Constanta, Romania*

*E-mail: cojocarus@yahoo.com*

**OBSERVATIONS
OF PLUTO
IN BUCHAREST**

**DURING 1932
AND 1967-1975:**

**PRECISE POSITIONS
AND MAGNITUDES**

GHEORGHE BOCSA

*Astronomical Institute of the Romanian Academy*

*Str. Cutitul de Argint 5, RO-75212 Bucharest, Romania*

*E-mail: gbocsa@aira.astro.ro*

**HARETU
AND THE
STABILITY OF
THE SOLAR
SYSTEM**

FLORIN DIACU ^{1},
TUDOR RATIU ^{2}

^{1} *Pacific Institute
for the Mathematical Sciences*

*and*

*Department of Mathematics and Statistics*

*University of Victoria, P. O. Box 3045*

*Victoria, B. C., V8W 3P4, Canada*

*E-mail: diacu@math.uvic.ca*

^{2} *Département
de mathématiques*

*École Polytechnique Fédérale de
Lausanne*

*CH-1015 Lausanne, Switzerland*

*E-mail: Tudor.Ratiu@epfl.ch*

**TO CELESTIAL
MECHANICS**

VASILE MIOC, MAGDA STAVINSCHI

*Astronomical Institute of the Romanian Academy*

*Str. Cutitul de Argint 5, RO-75212 Bucharest, Romania*

*E-mail: vmioc@aira.astro.ro, magda@aira.astro.ro*