Appendices A-C are only available in electronic form at http://www.aanda.org

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The Onsala 20 m telescope is operated by the Swedish National Facility for Radio Astronomy, Onsala Space observatory at Chalmers University of technology.

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... Telescope

The JCMT is operated by the Joint Astronomy Centre in Hilo, Hawaii on behalf of the present organizations: the Particle Physics and Astronomy Research Council in the United Kingdom, the National Research Council of Canada and the Netherlands Organization for Scientific Research.

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... XS

XS is a package developed by P. Bergman to reduce and analyze a large number of single-dish spectra. It is publicly available from ftp://yggdrasil.oso.chalmers.se

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... downloaded

http://www.iras.ucalgary.ca/~volk/getlrs_plot.html

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...Schöier et al. (2005b)

http://www.strw.leidenuniv.nl/~moldata

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... DUSTY

http://www.pa.uky.edu/~moshe/dusty/

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