Mental Note:

McLeod AG, Shen AC, Campbell KP, Michalak M, Jorgensen AO.
Frog cardiac calsequestrin. Identification, characterization, and subcellular distribution in two structurally distinct regions of peripheral sarcoplasmic reticulum in frog ventricular myocardium.
Circ Res. 1991 Aug;69(2):344-59.