Abu Bakr reported,
Then it will be said, "Call upon the truthful ones," and they will intercede. Then it will be said, "Call upon the prophets." A prophet will come accompanied by a group, another prophet with five or six followers, and another prophet with no one at all. Then it will be said, "Call upon the martyrs," and they will intercede for whomever they wish.When the martyrs have done so, Allah 
will say, "I am the Most Merciful of those who show mercy. Admit into My Paradise anyone who never associated anything with Me." So they will enter Paradise.
Azami 937
Hasanعن أبي بكر الصديق في حديث الشفاعة في الموقف وفيه
ثم يقال: ادعوا الصديقين فيشفعون، ثم يقال: أدعوا الأنبياء، قال: فيجيء النبي ومعه العصابة، والنبي ومعه الخمسة والستة، والنبي وليس معه أحد. ثم يقال: أدعوا الشهداء فيشفعون لمن أرادوا. وقال: فإذا فعلت الشهداء ذلك. قال: يقول الله عز وجل: أنا أرحم الراحمين، أدخلوا جنتي من كان لا يشرك بي شيئا. قال: فيدخلون الجنة.
Imam Ahmad narrated it (15), as did Abu Yaala (56), and Bazzar - Kashf Astar (3465) - all of them through Nadr bin Shumayl, who said, Abu Numaa told me, who said, Abu Hunaydah Bara bin Nawfal told me, from Walan Adawi, from Huzaifa, from Abu Bakr Siddiq, and he mentioned it in a long hadith already cited, and the objectionable element in it is placing the truthful ones ahead of the prophets.