What are algebraic systems and algebraic closure as defined by Kenjiro Shoda? Which are his main results on them? In On Utumi's ring of quotients, Canad. J. Math. 15(1963), 363-370, J. Lambek says:

As a matter of historical record, the minimal injective extension of a module is a special case of the "algebraic closure" of an algebraic system considered by K. Shoda in his paper Zur Théorie der algebraischen Erweiterungen, Osaka Math. J., 4 (1952), 133-144. 

Since I cannot read German, I cannot understand what the paper by Shoda says, although I think that he does defer the definitions to his previous papers Uber die allgemeinen algebraischen Systeme I-VIII (links provided below).
I would like to know:
1) What exactly his algebraic systems are (maybe the varieties of universal algebra?).
2) Which are his fundamental results about said systems (in these or other papers).
A published translation/review/summary would serve me perfectly. The MathSciNet reviews of the first papers are too vague, enumerating examples and talking about "certain operations", "various relations", etc.
Links to the I-VIII papers:
1) https://projecteuclid.org/download/pdf_1/euclid.pja/1195578672
2) https://projecteuclid.org/download/pdf_1/euclid.pja/1195573978
3) https://projecteuclid.org/download/pdf_1/euclid.pja/1195573940
4) https://projecteuclid.org/download/pdf_1/euclid.pja/1195573901
5) https://projecteuclid.org/download/pdf_1/euclid.pja/1195573626
6) https://projecteuclid.org/download/pdf_1/euclid.pja/1195573484 
7) https://www.jstage.jst.go.jp/article/pjab1912/19/9/19_9_515/_pdf
8) https://www.jstage.jst.go.jp/article/pjab1912/20/8/20_8_584/_pdf
 A: I have decided to not give a short answer to this question.
Although much of Shoda's work seems familiar, there are some twists that make it slightly different from the algebraic systems (universal algebras or algebraic structures) I have studied. Much as I would like to point to recent texts on Universal Algebra and say "you can get the concepts there", Shoda's emphasis and choices suggest something which I do not see clearly.  So I will attempt to summarize enough of the foundations to try to express the main results.  In particular, I will highlight what I think are the main points to grasp, in hopes that nonreaders of German can get the thrust of Shoda's development. I encourage others to comment and provide alternative readings if they are interested.  This posts deals with part I of the eight part development.
One key term I have not translated well (excuse lack of umlauts) is Verknupfung, which can mean short cut or abbreviation.  Behaviourally, this looks like a binary operation written in infix notation, and section 5 supports this.  There are ways of representing groups as structures with three binary operations (of type $\langle 2,2,2 \rangle$ in more modern terminology), and in section five the observation is made that (the variety of) groups expressed this way is definitionally equivalent to one in which two of the operations are term-defined using the third operation. Also noted are that if just the multiplication operation is used, the equational presentation so restricted only gives semigroups, and if one insists on commutativity for multiplication, one gets abelian groups,  So understanding the example in section five helps in reading the paper. However, there is the suggestion earlier that the shortcuts of interest are those that are invariant across a certain partition of the underlying set, and that they may not represent a binary operation so much as something that takes members from a pair of classes in the partition to another class of that partition, so reading Verknupfung as "infix binary operation" may miss something.
Another word with which I grapple is primitiv (feminine form in German is primitive). In section 3 it is applied to class of algebras that appear to me to be equationally defined, and so I think varieties. A further paragraph supports this, mentioning semi groups, groups, rings, lattices as primitive, but fields not so (because of division by zero), and integral domains are also not primitiv, the reason given that a quotient (homomorphic image) of an integral domain may not be an integral domain.  However, I am having difficulty understanding the literal translation.
I will edit this later to add more about paper I.
Gerhard "I Am Not A Roman" Paseman, 2017.10.24.
