Acoustic foam x bass trap for first reflections ?

Hi, my name is Régis from Brazil. I am currently putting together a home studio for myself, so I can record and, mostly, mix my own songs. I have read book “Mixing secrets - Mike Senior” and some chapters of book “Master handbook of acoustics”... they both recommend acoustic foam for treating first reflexions on the side walls. However, whenever I see more current recommendations from sound engineers, they tend to prefer bass traps other than the foams. Even if the foams are very thick (over 10cm)... what does your experience says about that? do you prefer foam or bass traps for treating first reflections? thank you very much