Negative Attack Value Modifier!?!

[Nethog]

Well I spent several days reading the manual cover-to-cover and started up the 1939 Storm over Europe campaign playing the Axis. I advanced the German 14th army to the hex just south of the city of Krakow. The Polish 10th Mechanized is defending the city. When look at the combat prediction window I see the following list for the German attack value: LAA=3--1=4. I assume the negative modifier is due to a Mechanized unit defending in a city? Or is there another explanation? When I look at the Polish unit's defense value for Hard, I see: Hard 2[1]. I know that normally the number in brackets is the improved value from tech research applied to the unit. But now I am wondering if this means something different when viewing the properties of enemy units, i.e. in this case a negative value due to the terrain the unit is sitting in?

[Sugar]

I guess that's right, at least tanks are indeed getting a malus fighting in urban terrain.