Based on archival data collected at the European Southern Observatory, La Silla, Chile.

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In particular note a clear warp excess around $l\sim240^{\circ}$ with respect to their fitted function.

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... $\sim$ -0.5

A recent study by Monaco et al. (2005) report on high resolution UVES spectroscopy showing a mean metallicity of [Fe/H $]=-0.41\pm0.20$ .

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...1994

Note that although the Freudenreich et al. paper was based on DIRBE data, they also derived the gaseous warp based on a re-analysis of the velocity-integrated HI emission maps from the survey of Weaver & Williams (1973).

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...2001)

Note that in this paper we do not use the Drimmel & Spergel (2001) model that is based on dust, since this predicts very high warping (cf. Fig. 2 of Yusifov 2004).

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... Galaxy

See also Fig. 1A and 1B of Evans et al. (1998).

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... motion

The near circular orbit of CMa is hard to account for in accretion models, usually preferring elliptical orbits. However, Crane et al. (2003) pointed out that this particular issue cannot rule out the accretion scenario since the tidal disruption of satellites depends on whether these satellites were originally born with near-circular orbits (Taffoni et al. 2003).

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... $R_{\rm GC}\simeq14.0$ kpc)

As demonstrated in Sect. 5, the results presented in this paper confirm earlier suggestions that a disk truncation hypothesis at $R_{\rm GC}\simeq14.0$ is neither needed nor justified.

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...2001)

Izotov & Thuan (2004) proposed a scenario in which young ( $\sim$ 500 Myr) galaxies like I Zw 18 are still being born in today's universe. Nevertheless, in Momany et al. (2005) we showed that I Zw 18 can be much older and that, at the moment, there is no photometric evidence of the existence of young galaxies.

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... catalogs

See however Momany & Zaggia (2005) reporting the presence of possible systematic errors in the UCAC catalog.

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... stars

Note also that in calculating W, Dinescu et al. (i) apply a mean $V_{\rm rad}$ value referring to the artificially produced $V_{\rm rad}$ peak at $109\pm4$ km s^-1 by Martin et al. (2004b); (ii) assume a distance of 8.1 kpc, different from the most recent determination (7.2 kpc) by Bellazzini et al. (2006); and (iii) combine the proper motion based on blue plume stars with $V_{\rm rad}$ values that are based on red clump stars.

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