Voltammetric signals for a one-electron (A) or two-electron (B) redox species adsorbed onto an electrode in the limit of slow scan rate. 
One-electron signal described in all text books, e.g. Bard. 

Two-electron signal described in [Plichon, V.; Laviron, E. "Theoretical study of a two-step reversible electrochemical reaction associated with irreversible chemical reactions in thin layer linear potential sweep voltammetry". Journal of Electroanalytical Chemistry and Interfacial Electrochemistry. 71 (2): 143–156. doi:10.1016/s0022-0728(76)80030-7]
Own work
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