Our observations were primarily a finding survey for strong southern millimeter sources, however we now briefly discuss the nature of our detected sources and examine those of special astrophysical interest.
The majority of the detected sources are flat-spectrum core-dominated
blazars (either quasars or BL Lac objects) at high redshift (roughly
between 
and 2.5). These objects are prime targets for
future multi-epoch, multi-frequency monitoring to further constrain the
properties of the highly beamed jet emission (Tornikoski et al.
1993). Many of the detected sources are strong at X-ray and
gamma-ray wavelengths, and several mechanisms have been proposed for
production of this high-energy emission via the inverse-Compton process
(Ghisellini & Madau 1996). These various models predict
different relationships between variability in the millimeter and
X-ray/gamma-ray, and joint monitoring observations in the different
wavebands may distinguish between these mechanisms (e.g. Grandi et al.
1996).
Although inverse-Compton models are generally successful in explaining
the spectral energy distributions of blazars, there are sources in
which the 
spectra peak strongly in the X-ray region; two
of these "MeV blazars" are detected in our survey. One is 
(Blom et al. 1995), and the other is 
or 
(Bloeman et al. 1995) (both mm-detected sources are
within the COMPTEL error box, although the former is thought more likely as
the source of gamma rays). These MeV-peaking sources can be explained by
exotic proton-initiated cascade or electron/positron annihilation
mechanisms (e.g. Roland & Hermsen 1995). These authors
stress the importance of obtaining VLBI proper motion velocities for these
sources which in combination with data on the MeV peak may strongly
constrain the jet physical parameters.
A number of the detected blazars have unusual properties which suggest
that it would be worth searching for spectral absorption along the line
of sight (e.g., Wiklind & Combes 1996a). The source 
at z=2.85 is one of the highest luminosity sources in the
centimeter band (having a flux density of over 7Jy at 8GHz), and shows
evidence for strong X-ray absorption (Elvis et al. 1992;
Serlemitos et al. 1994), implying a significant foreground
column density. Fugmann (1988) noted the extremely high
apparent luminosity of this object and the fact that it has many more nearby
companion galaxies than would be expected by chance, and argued that
gravitational lens amplification might be occurring. It is notable that a
number of detected mm-absorption systems have been found toward
gravitational lenses (Wiklind & Combes 1995, 1997). Three
blazar objects (
, 
, and possibly 
) show evidence for optical/uv absorption lines along the line of
sight (Junkkarinen et al. 1991), and these might also be
searched for molecular absorption, although searches of such systems have
proved unsuccessful to date (Wilkind & Combes 1996a).
Three of our detected sources are classified as galaxies, with their
optical continuum luminosity being dominated by starlight. The z=0.15
source 
contains a strong compact radio source and has an
optical spectrum showing high ionization emission lines and stellar
absorption lines characteristic of an evolved stellar population
(Tadhunter et al. 1993). The source 
is
identified with the nearby (approximately 80Mpc) galaxy NGC 6328, described
as high-luminosity elliptical with weak spiral structure (Veron-Cetty et
al. 1995); this galaxy is known to be very gas rich, containing over
1010 solar masses of HI. Australia Telescope images of this gas
have been made by Veron-Cetty et al., who speculate that this
galaxy is a recent merger product. Given our detection of a strong
millimeter continuum source it will be interesting to probe the gas
chemistry by looking for millimeter absorption and emission lines. The central
continuum source is interesting in its own right, as both the VLBI
morphology and the radio spectrum (which peaks in the gigahertz region)
are characteristic of so-called Compact Symmetric Objects (Wilkinson
et al. 1994), which are thought to be very young radio sources. The
detected 3mm flux density lies on a smooth extrapolation of the
centimeter spectrum and implies a spectral index of -0.7 between 8GHz
and 90GHz. One detection in our sample (
) is a known
gigahertz-peaked spectrum source (Cersosimo et al. 1994).
The final non-blazar that we have detected is the lobe-dominated FRII
source 
at z=0.028. This is one of the brightest objects in
the southern sky at centimeter wavelengths, and consists of a compact
core straddled by much brighter radio lobes (Fosbury et al.
1990; Norris et al. 1990).
The pointing position used was that of the
compact core as given by astrometric VLBI observations (Johnston et
al. 1995), and at 2mm in particular most of the extended emission
should lie outside of the SEST primary beam. The core has
a total flux of 0.82Jy at 8.4GHz (Tingay et al. 1996) and
hence our 2 and 3mm flux densities are consistent with a detection of this
flat spectrum core. Optical observations of show blue
optical emission from a patch of gas oriented almost along the initial radio
axis (Tadhunter et al. 1987). It has been argued, based on the
high optical polarization of this emission (di Serego Alighieri et
al. 1988), that this is evidence for reflected non-isotropic optical
emission along the radio axis, and that this object is misdirected
quasar (although Tingay et al. investigate the alternative explanation
of jet/cloud interactions). Optical spectroscopy of the nucleus (Tadhunter et al.
1993) shows only evidence for a stellar continuum with
no nonthermal continuum emission, consistent with blocking of the
putative quasar nucleus by a dense torus as proposed by the
quasar/radio-galaxy unified scheme. There is, however, some weak broad
line emission which may indicate that the source orientation and torus
geometry is such that part of the broad-line region can be seen. Given
our detection of the nucleus at millimeter wavelengths it will be
interesting to perform cm and mm spectroscopy to search for absorption
from molecular gas in a circumnuclear torus.