Fuad Al-Attar (Arabic: فؤاد العطار )has done some remarkable research on the Arabic books of Mirza Ghulam Ahmad, especially the plagiarism form dictionaries and books of ancient authors and poets.
Some of his articles can be found at http://alhafeez.org/rashid/arabic/arabic.htm.
Attached in one of his booklets. Below are a few of his other writings:.
Plagiarism from Maqamat Al-Hareeri
Abu Muhammad al-Qasim ibn 'Ali al-Hareeri was a writer who specialized in the literary form known as maqamat. He was born in 1054, near Basrah (Iraq) and died in 1122. He is primarily known for the witty style of his collection of tales, the Maqamat al-Hareeri, published in English as 'The Assemblies of al-Harîrî'
Mirza Ghulam Ahmad had read al-Hareeri's works, and included a lot of content in his writings, which may amount to Plagiarism. The 'borrowing' were mainly phrases and Arabic constructs. This is particularly interesting as he usually challenged others to write Arabic like he did. Despite copying from his works liberally, Mirza Ghulam Ahmad mentions him in [very unflattering terms].
Maqamat al-Hareeri is a set of tales (maqamat) about individual adventures, written in very archaic Arabic by Al-Hareeri, and with many difficult phrases and constructs. It can be downloaded from here: http://www.almeshkat.net/books/archive/books/alhareri.zip
Here are some sample pages from this book, where phrases have been matched to the writings of Mirza Ghulam Ahmad:
Describing an Opponent (Example 1)
Mirza Ghulam Ahmad describes his opponent Abdullah Atham. Each match is denoted with superscripts. The translation is literal, so that the English phrases can be matched:
Maqamat al-Hareeri p.7 (ORIGINAL)
He - the man - suffered the grin of horridness and the warfare of anxiety (1); he felt the sparks of the envious one and fallen down ill with the black cataclysms (2). This situation sustained till the palm of his hand was busted (3). The place became empty and the spring became dry. The light showers of spring took off, the throng vamoosed (4); the somnolence was discomposed, the circumstance was transmuted,the brood lamented (5) and the barn became empty... He fallen in the traps of the knavish(6) life and hit by the debasing penury till he wore the barefootedness as footgear, gobbled the lumps in the throat and experienced the doldrums(7)
Hujjat Ullah pp. 73-74 (COPY)
The hardship attacked him (Atham). This situation sustained till the palm of his hand was busted(3), the money was stolen and the brood lamented(5). He fallen in the traps of the knavish(6) grief and hit by the debasing penury till he wore the barefootedness as footgear, gobbled the lumps in the throat and experienced the doldrums(7). He spent his life with sorrow and fallen down ill with the black cataclysms(2). He immigrated then to India unassisted and blameful, and lived his life with injury and wound. He suffered the grin of horridness, the warfare of anxiety(1), the curses of cursers, and the abuse of abusers. This situation sustained till the problems continued, the trials increased, the throng vamoosed and the light showers of spring took off(4)
Another writing of the author is about 'Yelash' another name of God that Mirza Ghulam Ahmad claimed to have discovered, as an abbreviation of 'Ya la Shareek' (Arabic: O thou who has no partner)