Mu'tamir bin Sulayman narrated from his father that Imam Hasan al-Basri, may Allah have mercy on him, said regarding the woman in nifas: If she sees blood, she should wait for forty days, then perform prayer. The narrator said: And Imam Sha'bi, may Allah have mercy on him, said: She should wait for two months, then she will be under the ruling of a mustahadah (woman with irregular bleeding).
Hadith Referenceسنن دارمي / من كتاب الطهارة / 995
Hadith Gradingتحقیق (حسین سلیم أسد الدارانی):أثران بإسناد واحد وهو أسناد جيد، [مكتبه الشامله نمبر: 999]
Hadith Takhrijاس قول کی سند جید ہے۔ دیکھئے: [مصنف ابن أبى شيبه 367/4 -368]