I am looking to get more information about the mechanism of the $CaCl_2$ in the bacterial transformation. I read online about the topic but I didn't found any reverent information on the topic, I don't have access to most of the scientific publications. However, I found this website. According to this website, there is a lot of theory about the mechanism of calcium chloride in the bacterial transformation. Would it be possible to get a short scientific referenced explanation about the topic and I can or cannot be related to heat shocks?