Observations of Anomalous Microwave Emission from HII regions
  In this brief review, I give a summary of the observations of Anomalous
Microwave Emission (AME) from HII regions. AME has been detected in, or in the
vicinity of, HII regions. Given the difficulties in measuring accurate SEDs
over a wide range of frequencies and in complex environments, many of these
detections require more data to confirm them as emitting significant AME. The
contribution from optically thick free-free emission from UCHII regions may be
also be significant in some cases. The AME emissivity, defined as the ratio of
the AME brightness to the 100 micron brightness, is comparable to the value
observed in high-latitude diffuse cirrus in some regions, but is significantly
lower in others. However, this value is dependent on the dust temperature. More
data, both at high frequencies (>5 GHz) and high resolution (~1 arcmin or
better) is required to disentangle the emission processes in such complex
regions.
