اطلبوا العلم ولوباصين فإن طلب العلم فريضة على كل مسلم

uţlubu’l ílma wa law bi’ş şīn; fa-inna ţalaba’l ílmi farīđatun álā kulli muslim.
Seek knowledge, even if [you have to travel as far to find it] in China; for, seeking knowledge is obligatory for all muslims.

—-
Maqāşid al-Ĥasanah, Imām Sakhawī, entry #125.

Bayhaqi narrated this in Shuáb; Khatīb [Baghdādī] in Riĥlah etc; Ibn Ábd al-Barr in Jāmiý al-Ílm; and Daylamī.  All of them narrate through the ĥadīth of Ibn Áātikah Ţarīf ibn Sulaymān. And Ibn Ábd al-Barr [of the aforementioned] alone from the ĥadīth of Úbayd ibn Muĥammad from Ibn Úyaynah from Zuhri and both from Anas who narrates as a marfūú ĥadīth. This ĥadīth is weak from two aspects, and Ibn Ĥibbān said: “It is false.  There is no basis for this ĥadīth.” Ibn al-Jawzī mentioned it in Mawđūáāt; however, the second part of the ĥadīth will be mentioned along with its status, further in the chapter of ţā’a which is attributed to Ibn Mājah.