Soyuz TM-29 was a Russian manned spacecraft launched from the Baikonur Cosmodrome aboard a Soyuz 11A511U rocket. It docked with Mir on February 22 at 05:36 GMT with Cosmanauts Viktor Afanasyev of Russia,Jean-Pierre of France, and Ivan Bella of Slovakia aboard. Since two crew seats had been sold (to Slovakia and France), Afanasyev was the only Russian cosmonaut aboard. This meant that Russian engineer Avdeyev already aboard Mir would have to accept a double-length assignment. After the February 27 departure of EO-26 crew commander Padalka and cosmonaut Bella aboard Soyuz TM-28, the new EO-27 Mir crew consisted of Afanasyev as Commander, Avdeyev as Engineer and French cosmonaut Haigneré. 38th expedition to Mir.

Soyuz TM-29 became the first mission under Russian lead with three cosmonauts from three different countries. The new Mir-27 crew consisted of Viktor Afanasiyev as Commander, Sergei Avdeyev as Flight Engineer and French cosmonaut Jean-Pierre Haigneré.
Soyuz TM-29 docked with Mir on February 22, 1999 at 05:36 UTC. Since two crew seats had been sold (to Slovakia and France), Viktor Afanasiyev was the only Russian cosmonaut aboard. This meant that Russian Flight Engineer Sergei Avdeyev already aboard Mir would have to accept a double-length assignment.

Ivan Bella, executed during his mission the Slovak scientific program Stefanik. This consisted of the following items: Dozimetrie (radiation levels), Senso-asymmetrie (whatever that may be), Endotest (possibly hormonstudies), Metabolism, Training and as they say: Prepelica (Japanese quails). Experiments with these birds have been executed on Mir some years ago; not a single bird survived. He spoke with a specialist on earth and told that he was happy to be able to start with his work. Ivan Bella very quickly had adapted himself to the conditions of weightlessness and that he did not suffer any longer from the headache reported by him during his flight with Soyuz TM-28.
Ivan Bella had transported to Mir a number of eggs of that bird in the Incubator-T. The chickens in these eggs were scheduled to come out of the shell during the period of Ivan Bella's stay on board Mir. After arrival Ivan Bella had to transfer the eggs from the Incubator-T to the incubators on board Mir. While doing this he crushed 4 of them, but the other eggs safely were installed in the incubators and the chickens soon came out of their shells. There was a static incubator and one in a slow spinning centrifuge (to create more or less some gravity). Those who saw the light in the first incubator immediately enjoyed life and swallowed food and water. The poor birds who had to grow up in the centrifuge suffered from severe stress due to the darkness and low temperatures. The care for the birds has been taken over by the new crew. The experiment Prepelica is an enhanced continuation of the experiment of that kind executed by Anatoli Soloviyov during his flight. Japanese quails can produce eggs in a high frequency and the birds as will as the eggs are very rich of protein and so very suitable in the food of crews during long duration flights, for instance to Mars and beyond. It was unclear whether a part of the new-born quails would return by Soyuz TM-28.
Ivan Bella also executed the other experiments of the Stefanik program. Endotest indeed had something to do with hormone production and the physiology of endocrine glands. For this experiment he had to take blood samples. He also worked on the Dosimetry experiment, which studies the interactions of heavy ions in primary cosmic rays with different materials, i.e. biological tissues, integrated circuits etc. Other experiments were Senso - asymmetry, a study of motion sickness, Trenik (training) to determine the effects on the cardio-vascular system during weightlessness of long and intensive physical training on earth before the flight.
The program is named after Milan Ratislav Stefanik, a famous Slovak politician, astronomer, fighter pilot and general of the French army in WW-1, first Czechoslovak Secretary of Defense in the then just independent state. His career was pretty short for he died in a plane crash near Bratislava on May 04, 1919.