This is paper No. 21 in a refereed journal based on data from the ISOGAL project. Based on observations with ISO, an ESA project with instruments funded by ESA member states and with the participations of ISAS and NASA. Based on observations collected at the European Southern Observatory, La Silla Chile. Based on observations carried out with the IRAM 30-m telescope located at Pico Veleta. IRAM is supported by INSU/CNRS (France), MPG (Germany) and IGN (Spain).

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The full table is available in electronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/418/103

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...#77)

Throughout the paper for statistic computations only one infrared source, the targeted, is considered for these three positions. A second mid-infrared source is found within the IRAM beam at the position of the SiO sources #78 and #77 (separation $\sim$ 12 $^{\prime \prime }$ ), and at the position of the SiO sources #21 and #22 (separation of $\sim$ 15 $^{\prime \prime }$ ) (see Paper I) and is given in Table 2.

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