I find this an interesting building. It is at 620-622 Calle Florida, Buenos Aires and to my eye looks a bit Art Deco and a bit Art Nouveau. Let's start at the series of windows along the roofline. Their stepped tops are a bit deco. The zig-zag band below them is also a bit deco as is the arrangement of three squares on the façade of the central section. The decorative element looks formal, a bit nouveau yet the background of that particular element looks geometric and stepped, a bit deco.
A bit further down the semi-circular forms step down in size and adhere to the deco
rule of three but they are still a bit nouveau and the first set of balconies below that have a curly nouveau
question mark incorporated into the metalwork.
The balconies below that are quite nouveau (note that a few have been cut through to allow for air conditioners) but the balconies below that are, I would say, a bit deco.
Then we come to the pyramidal shapes at the base of the columns between the windows on the first floor. Are they a bit deco or a bit nouveau? I can't make up my mind.
Finally we come to the entrance. The stepping above the entrance is a bit deco as is the metalwork of the security gates and the window above them but the decoration above the doorway is certainly a bit nouveau.
An interesting building.