烏德里曾接受 Planetary Radio 的主持人麥特·卡普蘭訪問。在訪問中他提到了將裝設於甚大望远镜上的新儀器岩質系外行星與穩定光譜觀測階梯光柵攝譜儀（Echelle SPectrograph forRocky Exoplanet- and StableSpectroscopic Observations，ESPRESSO，暫譯），該設備或許可以讓天文學家以徑向速度法發現類地球系外行星，並且將在2010年以後5到10年內啟用。
- Dennis Overbye. 20 light years away, the most Earthlike planet yet. The New York Times. April 25, 2007 [2010-12-22].
The most enticing property yet found outside our solar system is about 20 light years away in the constellation Libra, according to a team of European astronomers. The astronomers said Tuesday that they had discovered a planet five times as massive as the Earth orbiting a dim red star known as Gliese 581. It is the smallest of the 200 or so planets that are known to exist outside of our solar system, the extrasolar, or exo-, planets. It orbits its home star within the so-called habitable zone where surface water, the staff of life, could exist if other conditions are right, said Stéphane Udry of the Geneva Observatory.
- JOHN NOBLE WILFORD. Another Cousin to Jupiter Is Found. The New York Times. June 19, 2002 [2010-12-22].
Dr. Stéphane Udry, a member of the team from the Geneva Observatory in Switzerland, said in an interview that what was missing in this planetary system — mammoth planets extremely close to the host stars — made it a more promising solar system analog than the one announced last week by the leading team of American planet hunters. The star the Americans found is accompanied by one and probably two Jupiter-size planets at closer distances than Mercury is from the Sun.
- Jeremy Manier. Just like home, yet light years from Earth. Chicago Tribune. April 25, 2007 [2010-12-22].
As with nearly all such planetary discoveries, astronomers could not observe Gliese 581 directly because it is invisible in the glare of its sun. Instead, the European group led by Stephane Udry and Michael Mayor calculated the planet's presence from its tiny gravitational tug on the star.
- Fifty New Exoplanets Discovered by HARPS. ESO. 12 September 2011 [2011-11-13].
- Joel Achenbach. Newly found 'exoplanets' are out of this world. Washington Post. October 20, 2009 [2010-12-22].
Astronomer Stéphane Udry of Geneva University said by e-mail that a new instrument under development, known as ESPRESSO (Echelle Spectrograph for Rocky Exoplanet- and Stable Spectroscopic Observations), "should allow us to detect Earth twins around solar-type stars, within 5 to 10 years." "Personally, I am convinced that planets are everywhere," Udry said. "Nature does not like void."