Dear Topaz,
Let me answer your question as well as I can.
You ask about reputable journals. Let me first give you a list of some of the publications which provide the background to this issue -
In the online Wikipedia Encyclopaedia there is an article entitled -
'Luchesi Authorship Controversy'.
http://en.wikipedia.org/wiki/Luchesi_authorship_controversy
You can see a list of various academic publications that are relevant to this issue. I personally provided a new English language version of a work called 'Works Falsely Attributed to Haydn and Mozart' (2005) which is not included in that list.
Please bear in mind that we are here discussing the entire life and career of Mozart - from that of his childhood, his youth, his early adulthood, his years before coming to Vienna, his arrival and marriage in Vienna, and the last 10 years or so of his short life. That's a lot of ground, you will agree !
I don't know where you stand on his early life. But it's very plain that many, many works atrributed to Mozart from his childhood were not, in fact, his own. This is a commonly known fact. Take, for example, the first 5 piano concertos. These are not compositions by the young Mozart. They're arrangements of works by various other composers. That's a plain fact. And this sort of thing happens for years.
You hear of course only one side of this story. The 'Mozart industry' is very powerful and it doesn't want you to hear the other side.
For a very long time, Austria (and the territory we today call Germany) was under the musical domination of Italians. It was Italians who had most of the music posts. Most Kapellmeisters were Italian and, of course, the invention of the symphony, the quartet, the quintet, etc etc were Italian. Those countries were part of what we call 'The Holy Roman Empire' where, up until 1773, the Jesuits (a military order of the Catholic Church) were in virtual control of music teaching. Mozart's father Leopold was Jesuit educated and Mozart himself received some academic teaching at home in Salzburg from Abbe Bullinger, himself a former Jesuit.
But in 1773 came a crisis. The Jesuits (who taught only in Latin) were officially banned. That caused a huge disruption in the musical Europe of that time in nations of the Holy Roman Empire. The Order was banished, forever, by the pope. For many crimes and for many times undermining kings and governments. So the Jesuits were forced to go underground or to emigrate. Some went to Russia (where they were temporarily accepted) and others stayed, hoping that one day they would be restored to power.
Officially they no longer existed. The Emperor himself banned them as soon as he heard the news from Rome. And from that time onwards their future seemed to be very uncertain.
But the Jesuits (of course) did not like losing all their huge power and influence. They fought to get it back. And this they did in many ways. First, by organising schools of theory in Padua (Italy), later in places like Mannheim etc. They wanted to keep their influence, even under the table, so to speak.
And, around this time, the idea was born that what would really get them back their favour would be if native German speaking composers were to become famous. So a plan was made to sponsor people like Gluck, and Haydn. Rich patrons did so. They became very famous. Their sponsors were rich lords like Esterhazy and the Emperor's brother Max Franz (the Elector of Cologne). Soon, people began to praise Gluck and Haydn as being 'German heroes' and this, in turn, helped to make 'Vienna - the city of music'. Great prestige for the Emperor (himself based in Vienna). This great idea was further helped by the development of the reputation of the young Mozart. It didn't really matter that, in fact, many works by Haydn and the young Mozart were actually by other composers. This was all secret. But, in truth, people like Sammartini and Luchesi (not famous today, of course) wrote many, many works which today are said to be 'Haydn's'.
This fakery was highly successful. Nobody cared too much and it wasn't exactly advertised. Later (in the 1780's) this 'manufactured' situation went to another level when several publishing firms for music opened with offices in Vienna - Artaria being one of them.
Let me continue with the story if I may.
Mozart (after many intrigues) finally came to Vienna. But notice, that in his first 3 years there he did not even keep a catalogue of his own compositions. That came later, in 1784.
And, in these early Vienna years, Mozart was looking for a permanent post.
The post Mozart really wanted was to be the Kapellmeister of the second greatest music chapel of the Holy Roman Empire. It was in Bonn - the seat of the Electorate of Cologne. This post was offered to him repeatedly by Max Franz, brother of the Emperor Leopold. But there was a problem. Max Franz had to wait for the death of the existing Elector (Max Friedrich). Only then could Mozart get to Bonn.
(This is the same Bonn chapel where, of course, the young Beethoven was to go).
Finally, in 1784, the old Max Friedrich died. Here was Mozart's big chance. The new elector Max Franz arrived in the city of Bonn. Being a great lover of music he ordered almost immediately an inventory of the chapel music to be made. (At that time, the existing Kapellmeister was the Italian named Andrea Luchesi - and he was on 1 year holiday in Italy with his Concertmaster).
Anyway, the inventory was made. Other people helped in the absence of Luchesi.
Luchesi was then told to hurry back from Italy. He arrived as fast as he could in Bonn but the inventory had already been completed.
During the inventory it was found that many pieces of music had NO NAME on the manuscript. Those making the inventory did not know whose they were. (In fact they were of course music personally written by Luchesi. It was normal for Kapellmeisters not to sign their own names on music they write during their term of office - the cantatas of JS Bach, for example, are rarely signed).
This large body of music with no name was simply put in to a pile and called 'anonymous'.
And this happened before Luchesi returned. It was spring of 1784.
Now - at this time (1784) Mozart was NOT known as a writer of symphonies. Nowhere do we find him having any reputation for writing symphonies. The two top writers of the time do NOT mention Mozart symphonies. In fact, in his entire lifetime Mozart had only ONE symphony published in his name (No.31) and it's not by him. (The Paris Symphony).
In this same year, the Inventory made at Bonn (which still survives) recorded hundreds and hundreds of pieces of music. But guess how many by Mozart were there ? The answer is NONE ! Not a single piece of Mozart was there. So you see how great the myth really is of Mozart's fame as a composer. Here is perhaps the greatest chapel in Germany at the time and not a single work by Mozart.
But the new Elector looked at this music and he noticed something extraordinary. He noticed that his Kapellmeister Luchesi was the true composer of works that were already in print in Haydn's name ! (These Luchesi had been selling to Haydn).
The new elector had a problem. He couldn't fire his own Kapellmeister and it might cause a huge scandal. Besides, he wanted Mozart to take Luchesi's place. But Luchesi couldn't be forced to resign. So a deal was made. Luchesi would from now on supply Mozart.
And that is what happened.
We know this is true. Years later the city of Bonn was occupied by the invading troops of Napoleon. But not before the music archives were parcelled up and removed from the city. Some of them eventually came to Italy - to relatives of the Elector. There they stayed, in Modena, until they were finally examined many decades later, by the librarian of the great Estense Library in Modena.
This Bonn material contained dozens and dozens of works by Haydn and Mozart !!! Many of these works had their original covers torn off and the name of 'Haydn' and 'Mozart' was now found on them. But there is no record that these symphonies ever came to Bonn during the lifetime of the chapel.
Among them are 9 'Mozart' symphonies. These include the 'Haffner' (35), the great G Minor (40), the 'Paris (31) and the 'Jupiter' (41). Symphonies that are today assumed to be by Mozart. In fact, the watermarks clearly show they come from Bonn. These symphonies are NOT by Mozart. Although they are (even in Modena) attributed to him.
Further proof is found at Regensburg. In that library you can see a copy of the symphony No. 31 ('Paris') containing the name of Mozart. But that name is written on top of a still legible name of 'Lucchese'.
I could continue for a long time. But this will hopefully be of some help in explaining the point. Others who supplied Mozart included composers such as Myslivececk, Kraus, Michael Haydn and others.
Very best wishes. Hope this helps.
Robert