The Securities and Exchange Commission has not necessarily reviewed the information in this filing and has not determined if it is accurate and complete.
The reader should not assume that the information is accurate and complete.

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
FORM 13F

FORM 13F INFORMATION TABLE
OMB APPROVAL
OMB Number: 3235-0006
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COLUMN 1 COLUMN 2 COLUMN 3 COLUMN 4 COLUMN 5 COLUMN 6 COLUMN 7 COLUMN 8
VALUE SHRS OR SH/ PUT/ INVESTMENT OTHER VOTING AUTHORITY
NAME OF ISSUER TITLE OF CLASS CUSIP (x$1000) PRN AMT PRN CALL DISCRETION MANAGER SOLE SHARED NONE
3M Company COM 88579y101 312 2,021 SH   SOLE   2,021 0 0
58.com Inc ADR COM 31680q104 87,673 1,368,605 SH   SOLE   1,368,605 0 0
AT&T Inc COM 00206r102 216 6,084 SH   SOLE   6,084 0 0
Altria Group Inc COM 02209S103 3,775 77,174 SH   SOLE   77,174 0 0
American Electric Power COM 025537101 820 15,485 SH   SOLE   15,485 0 0
American Express COM 025816109 108,426 1,395,088 SH   SOLE   1,395,088 0 0
Amgen COM 031162100 248 1,617 SH   SOLE   1,617 0 0
Apple Computer COM 037833100 1,681 13,406 SH   SOLE   13,406 0 0
Applied Materials COM 038222105 263 13,692 SH   SOLE   13,692 0 0
Arch Capital Group Ltd COM g0450a105 716 10,688 SH   SOLE   10,688 0 0
Athenahealth Inc. COM 04685w103 22,916 200,000 SH   SOLE   200,000 0 0
Automatic Data Processing COM 053015103 489 6,091 SH   SOLE   6,091 0 0
BP Amoco PLC ADR COM 055622104 238 5,948 SH   SOLE   5,948 0 0
Bank of America Corp COM 060505104 9,207 540,925 SH   SOLE   540,925 0 0
Bed Bath & Beyond Inc COM 075896100 419 6,075 SH   SOLE   6,075 0 0
Berkshire Hathaway - Cl A COM 084670108 1,939,520 9,468 SH   SOLE   9,468 0 0
Berkshire Hathaway - Cl B COM 084670702 658,044 4,834,647 SH   SOLE   4,834,647 0 0
Bio-Techne Corp COM 09073m104 250 2,540 SH   SOLE   2,540 0 0
Boeing COM 097023105 248 1,790 SH   SOLE   1,790 0 0
Bristol-Myers Squibb COM 110122108 244 3,670 SH   SOLE   3,670 0 0
Brown & Brown Inc. COM 115236101 85,692 2,607,791 SH   SOLE   2,607,791 0 0
CVS Corp. COM 126650100 2,617 24,953 SH   SOLE   24,953 0 0
Cabelas Inc. Cl A COM 126804301 170,381 3,408,985 SH   SOLE   3,408,985 0 0
Canadian Natural Resources COM 136385101 20,479 754,015 SH   SOLE   754,015 0 0
Caterpillar COM 149123101 5,808 68,479 SH   SOLE   68,479 0 0
ChevronTexaco Corp COM 166764100 446 4,626 SH   SOLE   4,626 0 0
Chubb COM 171232101 211 2,222 SH   SOLE   2,222 0 0
Citigroup Inc COM 172967424 332 6,016 SH   SOLE   6,016 0 0
Coca Cola Co. COM 191216100 33,622 857,046 SH   SOLE   857,046 0 0
Cognizant Technology Solutions COM 192446102 200 3,279 SH   SOLE   3,279 0 0
Colfax Corp COM 194014106 23,140 501,400 SH   SOLE   501,400 0 0
Colgate Palmolive Co. COM 194162103 232 3,548 SH   SOLE   3,548 0 0
Comcast Corp. Spl Cl A COM 20030n200 448 7,474 SH   SOLE   7,474 0 0
ConocoPhillips COM 20825c104 4,853 79,026 SH   SOLE   79,026 0 0
Costco Wholesale Corp COM 22160k105 97,612 722,733 SH   SOLE   722,733 0 0
Cresud SACIFYA Spon ADR Repstg COM 226406106 7,970 612,147 SH   SOLE   612,147 0 0
Ctrip.com International Ltd A COM 22943f100 7,262 100,000 SH   SOLE   100,000 0 0
Danaher Corp. COM 235851102 124,628 1,456,107 SH   SOLE   1,456,107 0 0
Diageo PLC Sponsored ADR COM 25243q205 3,492 30,090 SH   SOLE   30,090 0 0
DirectTV COM 25490a309 4,264 45,952 SH   SOLE   45,952 0 0
Discovery Communications Inc. COM 25468y107 56,543 1,700,044 SH   SOLE   1,700,044 0 0
Disney Walt COM 254687106 3,183 27,891 SH   SOLE   27,891 0 0
Du Pont E I De Nemours & Co. COM 263534109 3,566 55,762 SH   SOLE   55,762 0 0
Ebay Inc COM 278642103 254 4,220 SH   SOLE   4,220 0 0
Edison International COM 281020107 2,384 42,900 SH   SOLE   42,900 0 0
Emcor Group Inc COM 29084q100 80,013 1,674,964 SH   SOLE   1,674,964 0 0
Emerson Electric COM 291011104 279 5,035 SH   SOLE   5,035 0 0
Energizer Holdings Inc COM 29266r108 202 1,535 SH   SOLE   1,535 0 0
Expeditors Int'l of Wash. Inc. COM 302130109 5,434 117,859 SH   SOLE   117,859 0 0
Express Scripts Holding Co. COM 30219g108 436 4,905 SH   SOLE   4,905 0 0
Exxon Mobil Corp COM 30231g103 7,188 86,392 SH   SOLE   86,392 0 0
Fastenal Co COM 311900104 1,012,317 23,999,925 SH   SOLE   23,999,925 0 0
Fifth Third Bancorp COM 316773100 2,384 114,508 SH   SOLE   114,508 0 0
General Electric COM 369604103 6,018 226,490 SH   SOLE   226,490 0 0
Goldman Sachs Group Inc COM 38141g104 262,069 1,255,182 SH   SOLE   1,255,182 0 0
Google Inc Cl A COM 38259p508 312,699 579,029 SH   SOLE   579,029 0 0
Google Inc Cl C COM 38259p706 316,460 607,980 SH   SOLE   607,980 0 0
Graham Holdings Co. COM 384637104 3,500 3,256 SH   SOLE   3,256 0 0
Greenlight Capital Re Ltd Cl A COM G4095J109 12,886 441,764 SH   SOLE   441,764 0 0
Groupon Inc. COM 399473107 15,103 3,002,617 SH   SOLE   3,002,617 0 0
HDFC Bank Ltd ADR Repstg 3 Shs COM 40415f101 1,113 18,393 SH   SOLE   18,393 0 0
Heartland Express COM 422347104 2,044 101,057 SH   SOLE   101,057 0 0
Hexcel Corp COM 428291108 99,621 2,002,840 SH   SOLE   2,002,840 0 0
Home Depot COM 437076102 3,193 28,728 SH   SOLE   28,728 0 0
IAC Interactivecorp COM 44919p300 95,601 1,200,115 SH   SOLE   1,200,115 0 0
IBM COM 459200101 224,140 1,377,964 SH   SOLE   1,377,964 0 0
Idex Corp COM 45167R104 411 5,225 SH   SOLE   5,225 0 0
Idexx Laboratories Corp. COM 45168D104 518,459 8,083,238 SH   SOLE   8,083,238 0 0
Innerworkings Inc Com COM 45773y105 6,670 1,000,000 SH   SOLE   1,000,000 0 0
Interactive Brokers Group Inc COM 45841n107 41,660 1,002,415 SH   SOLE   1,002,415 0 0
Ishares India 50 ETF COM 464289529 229 7,674 SH   SOLE   7,674 0 0
JP Morgan Chase & Co. COM 46625h100 1,593 23,514 SH   SOLE   23,514 0 0
Jacobs Engineering Group Inc COM 469814107 162,060 3,989,652 SH   SOLE   3,989,652 0 0
Johnson & Johnson COM 478160104 7,539 77,357 SH   SOLE   77,357 0 0
Kinder Morgan Inc. COM 49456b101 370 9,630 SH   SOLE   9,630 0 0
Kraft Foods Group Inc. COM 50076Q106 1,483 17,424 SH   SOLE   17,424 0 0
LKQ Corp. COM 501889208 7,561 250,000 SH   SOLE   250,000 0 0
Lennox International Inc. COM 526107107 2,100 19,497 SH   SOLE   19,497 0 0
Leucadia Nat'l COM 527288104 400 16,471 SH   SOLE   16,471 0 0
Linear Technology Group COM 535678106 5,715 129,208 SH   SOLE   129,208 0 0
Lockheed Martin Corp. COM 539830109 511 2,750 SH   SOLE   2,750 0 0
Lowe's Companies Inc. COM 548661107 617 9,214 SH   SOLE   9,214 0 0
MRC Global Inc. COM 55345k103 55,243 3,577,935 SH   SOLE   3,577,935 0 0
Makemytrip Ltd COM v5633w109 28,701 1,458,400 SH   SOLE   1,458,400 0 0
Mastercard Inc COM 57636q104 506,642 5,419,792 SH   SOLE   5,419,792 0 0
McDonalds COM 580135101 13,002 136,767 SH   SOLE   136,767 0 0
McGraw Hill COM 580645109 386 3,840 SH   SOLE   3,840 0 0
Medtronic PLC COM G5960l103 362 4,880 SH   SOLE   4,880 0 0
Merck & Co. COM 58933y105 272 4,784 SH   SOLE   4,784 0 0
Microsoft COM 594918104 2,678 60,649 SH   SOLE   60,649 0 0
Mohawk Industries COM 608190104 530,638 2,779,666 SH   SOLE   2,779,666 0 0
Mondelez International COM 50075n104 2,332 56,680 SH   SOLE   56,680 0 0
Monsanto Co COM 61166w101 101,191 949,348 SH   SOLE   949,348 0 0
Novo Nordisk A/S ADR COM 670100205 4,479 81,800 SH   SOLE   81,800 0 0
O Reilly Automotive Inc COM 67103h107 809,097 3,580,392 SH   SOLE   3,580,392 0 0
Omnicom Group COM 681919106 195,988 2,820,383 SH   SOLE   2,820,383 0 0
PepsiCo COM 713448108 17,523 187,735 SH   SOLE   187,735 0 0
Perrigo Co PLC COM G97822103 271,120 1,466,859 SH   SOLE   1,466,859 0 0
Pfizer COM 717081103 368 10,967 SH   SOLE   10,967 0 0
Philip Morris Intl Inc. COM 718172109 7,321 91,317 SH   SOLE   91,317 0 0
Phillips 66 COM 718546104 3,181 39,491 SH   SOLE   39,491 0 0
Pioneer Natural Resources Co. COM 723787107 548 3,952 SH   SOLE   3,952 0 0
Praxair COM 74005P104 225,467 1,885,967 SH   SOLE   1,885,967 0 0
Precision Castparts Corp COM 740189105 702,022 3,512,391 SH   SOLE   3,512,391 0 0
Price T Rowe Group Inc COM 74144t108 314 4,045 SH   SOLE   4,045 0 0
Primerica Inc COM 74164M108 131,708 2,882,651 SH   SOLE   2,882,651 0 0
Procter & Gamble COM 742718109 12,471 159,400 SH   SOLE   159,400 0 0
Progressive Corp. Ohio COM 743315103 1,807 64,940 SH   SOLE   64,940 0 0
Public Storage Inc. COM 74460d109 460 2,493 SH   SOLE   2,493 0 0
Qihoo 360 Technology Co. ADR COM 74734m109 67,690 1,000,000 SH   SOLE   1,000,000 0 0
Qualcomm Inc COM 747525103 18,931 302,267 SH   SOLE   302,267 0 0
Range Resources Corp COM 75281a109 197,803 4,005,722 SH   SOLE   4,005,722 0 0
Republic Services Inc Cl A COM 760759100 492 12,555 SH   SOLE   12,555 0 0
Resource America Inc - (RESTRI COM 761195205 2,474 294,117 SH   SOLE   294,117 0 0
Resource America Inc Cl A COM 761195205 5,073 603,180 SH   SOLE   603,180 0 0
Robert Half Internat'l COM 770323103 389 7,000 SH   SOLE   7,000 0 0
Roper Industries Inc New COM 776696106 770 4,465 SH   SOLE   4,465 0 0
Royal Bk CDA Montreal Que COM 780087102 3,082 50,400 SH   SOLE   50,400 0 0
Royal Dutch Shell PLC Spon ADR COM 780259206 1,214 21,299 SH   SOLE   21,299 0 0
Schlumberger Ltd COM 806857108 3,402 39,466 SH   SOLE   39,466 0 0
Sherwin Williams Co. COM 824348106 1,460 5,307 SH   SOLE   5,307 0 0
Sirona Dental Systems Inc COM 82966c103 285,345 2,841,520 SH   SOLE   2,841,520 0 0
Soufun Holdings LTD ADR COM 836034108 8,481 1,008,500 SH   SOLE   1,008,500 0 0
Southwestern Energy Co COM 845467109 91,253 4,014,630 SH   SOLE   4,014,630 0 0
Stericycle Inc. COM 858912108 402 3,000 SH   SOLE   3,000 0 0
Suntrust Banks COM 867914103 1,342 31,203 SH   SOLE   31,203 0 0
TJX Cos - New COM 872540109 1,183,281 17,882,436 SH   SOLE   17,882,436 0 0
Thermo Electron COM 883556102 373 2,873 SH   SOLE   2,873 0 0
Third Point Reinsurance LTD COM g8827u100 36,160 2,451,509 SH   SOLE   2,451,509 0 0
Tiffany & Co COM 886547108 199,839 2,176,892 SH   SOLE   2,176,892 0 0
Trimble Navigation Ltd. COM 896239100 78,058 3,327,265 SH   SOLE   3,327,265 0 0
U.S. Bancorp New - Del. COM 902973304 1,128 25,999 SH   SOLE   25,999 0 0
Union Pacific COM 907818108 9,293 97,446 SH   SOLE   97,446 0 0
United Technologies COM 913017109 208 1,873 SH   SOLE   1,873 0 0
Valeant Pharmaceuticals Intern COM 91911k102 7,527,342 33,884,050 SH   SOLE   33,884,050 0 0
Verisk Analytics Class A COM 92345Y106 4,273 58,730 SH   SOLE   58,730 0 0
Verizon Communications COM 92343v104 329 7,056 SH   SOLE   7,056 0 0
Visa Inc Class A COM 92826C839 227,610 3,389,577 SH   SOLE   3,389,577 0 0
WPP PLC New ADR COM 92937a102 320 2,840 SH   SOLE   2,840 0 0
Wal-Mart Stores COM 931142103 154,347 2,176,040 SH   SOLE   2,176,040 0 0
Waters Corp COM 941848103 263,239 2,050,465 SH   SOLE   2,050,465 0 0
Wells Fargo & Co. New COM 949746101 13,185 234,445 SH   SOLE   234,445 0 0
West Pharmaceutical Svcs Inc C COM 955306105 59,006 1,015,951 SH   SOLE   1,015,951 0 0
Yandex NV Shs COM n97284108 55,198 3,626,693 SH   SOLE   3,626,693 0 0
Yelp Inc. COM 985817105 4,634 107,700 SH   SOLE   107,700 0 0
Zoetis Inc. COM 98978v103 7,288 151,149 SH   SOLE   151,149 0 0
Constellation Software Inc. COM 21037x100 107,047 269,486 SH   SOLE   269,486 0 0
Jardine Matheson Hldgs (U$.25 COM G50736100 205 3,600 SH   SOLE   3,600 0 0
Ryanair Hldgs PLC Spon ADR COM 783513104 579 8,121 SH   SOLE   8,121 0 0
Senvest Capital Inc. COM 81731l109 5,460 35,000 SH   SOLE   35,000 0 0