
The later scholars of hadith used a letter and number symbol system to identify which Imams used the narrator in their books of hadith. This system is utilized in the encyclopedic biographical works such as Tahthib At-Tahthib of Hafith Ibn Hajr, his Taqrib , Adh-Dhahabi in his Al-Mizan and other works of immense benefit in the science of Hadith.
Examples:
The following are a few examples of the Letter & Number Symbol system:
At the end of the entry of As-Sa’ib An-Nukri you find the two letters مد . This is the symbol system. Now if you use the key below you will be able to determine what book of hadith meem daal represents; Abu Dawud’s Marasil.
Another example:
In this example ‘Amir ibn ‘Ubdah Al-Baahili is used. At the end of his entry you find the letters خت . Now using the key below you will see that khaa taa stands for Bukhari’s Sahih in Mu’allaq form.
Another example:
In this example I have used the entry Abdul-Aziz ibn Abi Bakra Ath-Thaqafi who is, as Ibn Hajr states, Saduq. At the end of the entry you can see the symbols خت د ت ق . Note that one should be careful not to combine letters or else it will change the referencing and one will be mistaken when verifying or utilizing the symbol system.
So using the code system below one can determine that Abdul-’Aziz’s narrations are found in Bukhari’s Sahih in Mu’allaq form, Abu Dawud’s Sunan, Tirmidhi’s Sunan, and the Sunan of Ibn Majah.
Last Example is for You to Figure Out
This narrator’s name is Qartha’, the only narrator named such in the books of hadith. He is Saduq (honest) according to Hafith Ibn Hajr in this entry. What books of Hadith narrate through him as stated by Hafith Ibn Hajr?
Please post your findings in the comments of this thread so that I know someone understands the system!
The following is a general key as mentioned by Hafith Ibn Hajr Al-’Asqalani in his Intro to Taqrib At-Tahthib:
Codes for Imam al-Bukhari:
خ – Bukhari’s Sahih
خت – Bukhari’s Sahih in Mu’allaq form
بخ – Bukhari’s Adab Al-Mufrad
عخ – Bukhari’s Khalq Af’al Al-’Ibad
ر – Bukhari’s treatise “Juza’ Al-Qira’at”
ي – Bukhari’s Rafa’ul Yadayn
Codes for Imam Muslim
م – Muslim’s Sahih
مق – the Muqaddimah of the Sahih of Imam Muslim
Codes for Imam Abu Dawud
د -Abu Dawud’s Sunan
مد – Abu Dawud’s Marasil
صد – Abu Dawud’s Fadaa’il Al-Ansaar
خد – Abu Dawud’s Naasikh
قد -Al-Qadir
ف – At-Tafarrud
ل – Masaa’il
كد – Musnad Maalik
Codes for Imam Tirmithi
ت – Sunan
تم – Ash-Shama’il
Codes for Imam An-Nasa’i
س -Sunan
عس – Musnad ‘Ali
كن – Musnad Imam Malik of Imam An-Nasa’i
Hafith Shu’ayb Al-Arna’ut mentions two more that Ibn Hajr does not that are sometimes used for Imam An-Nasa’i:
سي – ‘Amal Al-Yawm wal-Laylah
ص – Khasa’is ‘Ali
Codes for Imam Ibn Majah:
ق -Sunan
فق – Tafsir
If the narrator is within all of the six books of hadith the letter ع is used. If the number 4 is used then it is in the four sunan without the two Shayks (i.e. Bukhari and Muslim).
In other than these works the Hafith Ibn Hajr uses تميز (tamayyaz).
Edited 5-30-09

I have always wondered why the Subcontinenters of Asia, mainly the Deobandis, refrained from translating Sunan At-Tirmidhi. They translated Sunan Abu Dawud (Prof. Ahmad Hasan), Sunan An-Nasa’i As-Sughra (the smaller version translated by Muhammad Iqbal Siddiqi), Sahih Muslim and Mishkat Al-Masabih (at least a few volumes of it) by Abdul Hameed Siddiqi, Sunan Ibn Majah (Translated by M. Tufail Ansari) , Muwatta of Imam Malik (Translated by Muhammad Rahimuddin) and other smaller texts such as Riyad us Salihin and the 40 of Imam An-Nawawi. Yet, for some odd reason, no one ever took it upon themselves, at least to my knowledge, to translate one of the most valuable canonical works of hadith, Sunan At-Tirmidhi. For years I wondered as to why this fantastic tome, full of fiqh and hadith gradings would be ignored by the translators. I always made the excuse that it was simply because it was such a daunting task, though I never really beleived such an excuse.