... observables

In memory of Ruggiero de Ritis, deceased September 2000.

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... lens

In this paper we use the terms lens and MACHO as synonymous, even if the lens may be also a visible star.

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... source

This is a reasonable hypothesis if the source is in the Magellanic Clouds, but it is not if the target of observations is M31. However, in this paper we limit ourselves to observations towards LMC only.

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... density

Note that the $\rho_{\odot}$ previously introduced and $\rho _{\odot }^{(\rm s)}$ are equal only for models with q = 1; in general, the link between these two quantities is given by: $\rho_{\odot} = \rho_{\odot}^{(\rm s)} \frac{e}{q \sin^{-1}{e}}\cdot$

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... unlikely

Negative values of $\alpha$ means that the MF is increasing which has never been observed, whilst values greater than 5.0 are quite unusual.

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... considered

A complete list of the solutions for each model, comprising also the rejected ones, and further details on the numerical procedures are available on request to the authors.

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