The statements of the early Church Fathers regarding the doctrine of the Trinity (pre-Nicea) In an article answering Georg Kaplan's 1 denials of the Trinitarian doctrine, Ken Temple states :

Even if the early Church had never applied the title θεός to Jesus, his deity would still be apparent in his being the object of human and angelic worship and of saving faith; the exerciser of exclusively divine functions such as creatorial agency, the forgiveness of sins, and the final judgment; the addressee in petitionary prayer; the possessor of all divine attributes; the bearer of numerous titles used of Yahweh in the OT; and the co-author of divine blessing.
Faith in the deity of Christ does not rest on the evidence or validity of a series of ‘proof-texts’ in which Jesus may receive the title θεός but on the general testimony of the NT corroborated at the bar of personal experience.147
Apologetics and Agape - Wordpress - March 19, 2018

Nevertheless he publishes a list of texts as an example.
However what attracted my attention and what prompts my question is his answer to the objection that the doctrine of the Trinity was formed in later centuries than the early church and the objector claims that the early church knew nothing of it until Nicea.
So Ken Temple further states :

... Ignatius, Irenaeus, Tertullian, Origen, and Athanasius and Hillary and others had expressions of the Trinity in centuries (and at the same time – Athanasius and Hillary) before Gregory of Nyssa. Ignatius is clear on the Deity of Christ in early second century (around 107-110 AD) and has a simple expression of the Trinity.

So, Ken Temple then quotes from Ignatius (writing in 107-110 AD), which I shall not copy, it is in the linked document.
But all he says of Tertullian is :

Also, Tertullian, around 190-220 AD, used the basic words, “Trinitas Unitas” (three in one) and “persona” (the Latin equivalent of hypostatis) over 1 century before the Cappadocian Fathers, as did Origen around 250 AD.

My question is - Are there more susbstantial references available on this subject from Tertullian and Origen and Irenaeus ?

1 Georg Kaplan, a professed Unitarian, seems to be linked to the pseudonyms 'Gregory Blunt' and 'Thomas Pearne'. (Although, elsewhere it is spelt 'Kaplin').
Edit : Comment suggests that this is a third layer of pseudonym.
I found the following quotes on the doctrine of the Trinity:
IRENAEUS –

“He is Himself in His own right God and Lord and Eternal King and Only
begotten and Incarnate Word, proclaimed as such by all the prophets
and by the Apostles and by the Spirit Himself… The Scriptures would
not have borne witness to these things concerning Him, if, like
everyone else, He were mere man.” (Against Heresies by Iranaeus, 3.10
pp1-2, Jurgens, Vol. 1)
“[The Gnostics] transfer the generation of the uttered word of men to
the eternal Word of God, attributing to Him a beginning of utterance
and a coming into being in a manner like to that of their own word. In
what manner, then, would the Word of God – indeed, the great God
Himself, since He is the Word – differ from the word of man, were He
to have the same order and process of generation?” (Ibid. 2:13.8)

ORIGEN –

“Although He was God, He took flesh; and having been made man, He
remained what He was, God… For we do not hold… that some part of the
substance of God was converted into the Son, or that the Son was
procreated by the Father from nonexistent substances, that is, from a
substance outside Himself, so that there was a time when He did not
exist.” (Fundamental Doctrines by Origen, Ibid., p1, pref.3-4)

TERTULLIAN –

“God alone is without sin. The only man without sin is Christ; for
Christ is also God.” (The Soul by Tertullian, 41.3, Jurgens, Vol. 1)
“But Christ,” they [the Gnostics] say, “also bore the nature of an
angel.” For what reason? And why did He take human nature? … Christ
bore human nature in order to be man’s salvation… There was no such
reason why Christ would take upon Himself angelic nature.” (Ibid.
14.1)

Now let me quote from another book which deals with Tertullian and his theology – The Story of Christian Theology by Roger E. Olson, Apollos, 1999.

“Tertullian’s massive critique Against Praxeas was written after
Tertullian had defected to Montanism, but its influence throughout the
Western Christian churches was ‘immediate and permanent.’ Praxeas was
perhaps the first Christian theologian to attempt to explain the
doctrine of the Trinity in systematic detail. In the process, however,
he apparently explained away the real ontological threeness of the
persons of God. That is, Praxeas denied that Christians believed in
three distinct identities or even relations within the one divine
being… Praxeas’s view later came to be known as modalism and was
revived by another later teacher of Christians in Rome named
Sabellius… Tertullian perceived this modalistic explanation of the
triunity of God as a dangerous heresy and declared in typical fashion,
“Praxeas did a twofold service for the devil at Rome: he drove away
prophecy, and he brought in heresy; he put to flight the Paraclete and
crucified the Father”. (Tertullian, quoted in Justo Gonzalez, A
History of Christian Thought, vol. 1, From the Beginnings to the
Council of Chalcedon, rev. ed. (Nashville: Abingdon, 1992) p.178.)
[Page 92 of Olson’s book.]
“Tertullian strove to explain why Christians worship Jesus Christ
rather than Caesar or any other so-called god and yet at the same time
insist that God is one and heavenly. In order to explain this, he
turned to the often-used concept of the Logos of God and appropriated
an analogy that would become a favorite one for Christian thinkers
wrestling with this issue. The Logos, Tertullian carefully explained,
is both God and God’s offshoot through which he relates to creation.
This Logos is, of course, Christ, the Son of the Father. Tertullian
used the sun analogy to explain their relationship:  ‘This ray of God,
then, as it was always foretold in ancient times, descending into a
certain virgin, and made flesh in her womb, is in his birth God and
man united’. (Tertullian Apology 21 ANF 3) [Page 93 of Olson’s book.]
“In Against Praxeas Tertullian provided a fairly clear statement of
this organic monotheism: ‘All [three – Father, Son and Holy Ghost] are
of One, by unity (that is) of substance; while the mystery of the
dispensation is still to be guarded, which distributes the Unity into
a Trinity, placing in their order the three Persons – the Father, the
Son, and the Holy Ghost: three, however, not in condition, but in
degree; not in substance, but in form; not in power, but in aspect;
yet of one substance, and of one condition, and of one power.”
(Tertullian Against Praxeas 2.) [Page 96 of Olson’s book, which also
has more on Irenaeus and Origen – I do recommend this book.]