!!!! Ferrous and ferric extras

==== Wikipedia

https://en.wikipedia.org/wiki/Ferrous @@ Ferrous
https://en.wikipedia.org/wiki/Iron(III) @@ Iron(III)

==== References

https://www.annualreviews.org/doi/abs/10.1146/annurev-arplant-042811-105522 @@ Kobayashi 2012 Iron uptake higher plants
https://link.springer.com/article/10.1023/A:1024953027726 @@ Weiss 2003 Fe(II) oxidizing & reducing in wetland plant roots
https://books.google.com.br/books?id=rk3gBAAAQBAJ&lpg=PA111&ots=rrJjhLOFr9&lr&pg=PA111#v=onepage&f=false @@ Robb book Metals and micronutriens uptake by plants
http://www.plantphysiol.org/content/119/3/1107.short @@ Wirén 1999 Nicotianamine cleatees both II and III
https://www.journals.uchicago.edu/doi/abs/10.1086/335995 @@ Bell 1950 Response of maize to II, III
https://academic.oup.com/jxb/article-abstract/28/3/678/587444 @@ Green 1977 Oxidation of II by rice roots, tolerance? 
https://onlinelibrary.wiley.com/doi/full/10.1111/j.1365-313X.2005.02624.x @@ Ishimaru 2006 Rice takes up  both III as siderophore and as II
https://www.researchgate.net/publication/310822713_Ocean_Iron_Fertilization_Experiments_Past-Present-Future_with_Introduction_to_Korean_Iron_Fertilization_Experiment_in_the_Southern_Ocean_KIFES_Project @@ Yoon 2016 Korean Iron fertilization experiment S Ocean
https://onlinelibrary.wiley.com/doi/abs/10.1111/j.1365-3040.1978.tb02037.x @@ Brown 1978 Mech iron upt in plants
https://www.tandfonline.com/doi/abs/10.1080/01904168209363012 @@ Lindsay 1982 Chem of iron and aval to plants
https://www.tandfonline.com/doi/abs/10.1080/01904160009382137 @@ Zaharieva 2008 II uptake induced in strategy 1 under Fe deficiency
https://www.sciencedirect.com/science/article/pii/001346868880152X @@ Kálmán 1988 Hidration of II in solution
https://www.ajol.info/index.php/bcse/article/view/54752 @@ Mohammed 2010 computer sim Hydration dynamics of II in solution
https://iopscience.iop.org/article/10.1088/0953-8984/4/3/006 @@ Herdman 1992 hydration of 1 molar II chloride in heavy water