Phillip Helbig
"Constraints in the λ₀–Ω₀ plane from gravitational lensing"
in New Cosmological Data and the Values of the Fundamental Parameters, International Astronomical Union. Symposium No. 201 (ADS: 2005IAUS..201.....L)
A. Lasenby & A. Wilkinson (eds.),
San Francisco: Astronomical Society of the Pacific, p. 245 (2005)
ISBN 978-1-58381-212-9; 1-58381-212-1
ADS: 2005IAUS..201..245H | | Google Scholar