Which design pattern has been used in excel spread sheet?

Today me and my team analyzing excel sheet and try to evaluate the its architecture. For resolving the sequence of its formula, I believe they used command pattern with chain of responsibility design pattern for ordering of formula execution. The only thing I want to understand is how excel maintain the sequence of formula execution as one formula cell(f1) can be used as input in another formula cell(f2), so f1 has to execute first before f2 and there should not be a cyclic dependency in all formula. Any help will be appreciated.