Caution: Translations of Quran and Ḥadīth may lead to possible misapplications and misinterpretations. This site is intended for students of sacred knowledge that are proficient in comprehending classical Arabic and have a strong foundation in Islamic sciences. Also note that religious injunctions rely on several aspects beyond what one may glean through reading individual aḥādīth.
bayhaqi:7983

[Machine] Narrated Sufyan, and he added to it: "When you see the new moon at the beginning of the day, do not break your fast until two just men witness that they sighted it yesterday evening." Abu Bakr bin Al-Harith Al-Faqih informed us: Ali bin Umar Al-Hafiz narrated to us from Abu Bakr An-Naysaburi from Hajib bin Sulaiman from Muammal bin Ismail from Sufyan from Mansour, and he mentioned it. Ali said to us: Abu Bakr told us, "If Muammal narrates it to you, then it is a rare narration. And Imām Abdul Rahman bin Mahdi contradicted it." The Sheikh said, "And this wording has been narrated to us."  

البيهقي:٧٩٨٣وَرَوَاهُ مُؤَمَّلُ بْنُ إِسْمَاعِيلَ

عَنْ سُفْيَانَ فَزَادَ فِيهِ فَإِذَا رَأَيْتُمُ الْهِلَالَ أَوَّلَ النَّهَارِ فَلَا تُفْطِرُوا حَتَّى يَشْهَدَ رَجُلَانِ ذَوَا عَدْلٍ أَنَّهُمَا أَهَلَّاهُ بِالْأَمْسِ عَشِيَّةً أَخْبَرَنَاهُ أَبُو بَكْرِ بْنُ الْحَارِثِ الْفَقِيهُ أنبأ عَلِيُّ بْنُ عُمَرَ الْحَافِظُ ثنا أَبُو بَكْرٍ النَّيْسَابُورِيُّ ثنا حَاجِبُ بْنُ سُلَيْمَانَ ثنا مُؤَمَّلُ بْنُ إِسْمَاعِيلَ ثنا سُفْيَانُ حَدَّثَنِي مَنْصُورٌ فَذَكَرَهُ قَالَ عَلِيٌّ قَالَ لَنَا أَبُو بَكْرٍ إِنْ كَانَ مُؤَمَّلٌ حَفِظَهُ فَهُوَ غَرِيبٌ وَخَالَفَهُ إِمَامُ عَبْدِ الرَّحْمَنِ بْنِ مَهْدِيٍّ قَالَ الشَّيْخُ وَهَذَا اللَّفْظُ قَدْ  

رَوَاهُ شُعْبَةُ عَنْ سُلَيْمَانَ بْنِ مِهْرَانَ الْأَعْمَشِ عَنْ أَبِي وَائِلٍ